Aluminium Alloys

Welding is a manufacturing process, which uses heat or pressure to form a homogeneous weld when joining homogeneous or heterogeneous metal materials or thermoplastics. The last decade has been characterized by the intensive development of unconventional welding processes, which use friction as an energy source, and in developed countries have taken primacy over conventional welding processes. The modern welding process, known as Friction Stir Welding (FSW), offers many advantages over conventional Tungsten Inert Gas (TIG) and Metal Inert Gas (MIG) processes, both in terms of weld quality and environmental protection and in terms of saving time and materials needed to perform quality welding. This paper presents TIG, MIG and FSW welding technologies, with all the advantages and disadvantages, and the possibilities of their application in welding AA6082-T6 aluminum alloy (6xxx series), characterized by medium strength and outstanding corrosion resistance.

The objective of this work is the investigation of milling process variables which resulting in optimal values of the surface roughness and material removal rate during machining of 7024 Al-alloy. The machining operation implemented on C-TEK CNC milling machine. The effects of the selected parameters on the chosen characteristics have been accomplished using Taguchi’s parameter design approach; also ANOVA had been used to evaluate the contribution of each parameter on the process outputs. Different feed rates are used ranging from (60, 80 and 100) mm/min, found that high feed rates gives a high material removal rates and good surface roughness. On the other hand, using three levels of spindle speeds found that a higher spindle speeds gives better surface roughness with a little effect on MRR. The process results showed that maximum MRR achieved (2.40) mm3/min when machining feed rate (100) mm/min, spindle speed (1000) r.p.m, and depth of cut (0.6) mm while good surface roughness (0....

The thickness of the adhesive has a major influence on the shear strength of bonded assemblies. This work is based on a study of the fatigue behavior of two cracked aluminum (2024 T351) plates repaired by patch (graphite/epoxy) under cyclic loading. For this we used a computer code to study the propagation of fatigue cracks to predict the life of the plates repaired named AFGROW. The first plate was repaired using an adhesive made from date palm waste whereas the second plate was repaired using FM-73 adhesive. The results obtained from this study show that, despite the low shear modulus of the adhesive made from date palm waste and the very low film thickness, the joint bonded with the latter gives good joint strength and a lifetime (number of cycles) similar to the joint bonded with the FM-73 adhesive when the thickness of the joint of the adhesive is greater than that of the adhesive made by the waste of the date palm. This shows that the strength of the bonded joint increases rapidly from very low thicknesses (less than a few hundredths of a millimeter). Finally, we recommend using the adhesive made from date palm waste for patch repair as well as for applications such as lightweight construction, electric vehicles or solar panels.

Aluminium alloys are used as lightweight materials especially in the aerospace and automotive industries. They have a number of properties such as high corrosion resistance due to the surface oxide coating, low relative weight and better castability. At normal temperatures, metal oxides are more resistant than the metal itself. The oxide layer is much thinner than the metal but protects it from interacting with the air. The kinetics of oxidation processes is the subject of the current work. As the temperature rises, the oxidation process usually proceeds in the presence of water vapour, and its rate depends on various factors, including the initial oxide layer and oxidation kinetics. The values of the oxidation exponent n аrе calculated for aluminium ribbons with different contents of Fe, Mg and Sb. Their influence on the intensity and two-stage tendency of the oxidation process is established.

Mechanical loading causes material deformation, resulting in changes in mechanical properties due to microstructural alterations such as the multiplication of dislocations and evolution of grain morphology. Blast loading, a condition where materials deform at high strain rates, results in significant plastic deformation. This rapid deformation induces intense mechanical stresses, causing complex microstructural changes that influence the mechanical behavior and performance of the materials. Consequently, designing structures to withstand blast loading requires understanding the relationship between microstructure and property evolution. As the primary objective of this study, post-localized blast experiments have been conducted to elucidate the variability in microstructural response of Austenitic stainless steel (ASS) 316 L, characterized by its face-centered cubic crystal structure. Localized blast loads were applied to square test plates, 2 mm thick, with a circular exposed area of 106 mm in diameter. Quantitative mechanical property data from key zones within the deformed dome were determined through using a novel micro-tensile testing approach and nanoindentation tests. Electron backscatter diffraction (EBSD) in scanning electron microscopy (SEM) technique was employed to characterize the microstructural changes in the selected samples. The results revealed that blast loading induced complex mechanical and microstructural changes in ASS 316 L, including enhanced material strength, reduced ductility, and significant alterations in grain orientation and misorientation distributions. The materials underwent significant strain hardening due to the increased stress and deformation, resulting in a more resistant to plastic deformation and the greatest internal strain accumulations. Texture analysis underscored the influence of deformation geometry, with Goss and Copper emerging as predominant texture components.

The Artificial Intelligence is revolutionizing the materials science arena, enabling the discovery, design, and optimization of innovative mechanical and bioinspired materials. This review consolidates insights from recent developments in AI-enabled methods to improve properties such as stiffness, strength, thermal performance, and durability of materials. This work focuses on diverse applications, including nanogenerator, Graphene-based electrodes, composites, metamaterials, and polymers, with an emphasis on how generative AI, deep learning, and machine learning approaches optimize material configurations to enhance prediction accuracy and streamline manufacturing processes. It further demonstrates the ability of AI in reducing redundancies, minimizing defects, and improving material quality by integrating into additive manufacturing, metamaterials design, and electrochemical energy storage. The results underline the importance of AI in pushing innovations within these fields: sustainable polymers, advanced ceramics, and precision manufacturing rendering transformative solutions for challenges in materials engineering.

The results of examinations of the influence of titanium-boron inoculant on the solidification, the microstructure, and the mechanical properties of AlZn20 alloy are presented. The examinations were carried out for specimens cast both of the non-modified and the inoculated alloy. There were assessed changes in the alloy overcooling during the first stage of solidification due to the nuclei-forming influence of the inoculant. The results of quantitative metallographic measurements concerning the refinement of the grain structure of casting produced in sand moulds are presented. The cooling rate sensitivity of the alloy was proved by revealing changes in morphology of the α-phase primary crystals. Differences in mechanical properties resulting from the applied casting method and optional inoculation were evaluated.

The wear of component is regularly a serious issue prompting the product provision period. Wear prophecy is consequently a vital area in technology. The wear recreation method with profitable software ANSYS 10.0 finite element (FE) was implemented with the linear wear Archard equation. The wear of commercially available brake pad sliding against Ti-6Al-4V disc was analyzed with FEM under different operating conditions such as normal load, sliding velocity, sliding distance and operating temperature. A 3D-8 node structural element (SOLID 185) and 3D-8 node surface-to-surface contact elements (Target 170 and Contact 174) is used to analyze the wear of pin and disc. Using ideal boundary conditions, the simulation predicts the wear rate, wear depth, contact pressure and contact friction stresses under different operating conditions at the contact zone.

In this research, the main aim is to focus the enhancement of aluminium-based metal matrix composites for improving the attributes of light weight metals, aerospace structures and other tailor blank material properties. By this way, the friction stir processing (FSP) was the suited alternate technique to enhancing the mechanical attributes and superior microstructural amendment in the processed MMCs. Terefore, this study investigates the dispersion of ceramic-based strengthening particles of chromium oxide (Cr 2 O 3) in the aluminium base matrix of A356 alloy. During the processing, the diferent tool pin sizes having the conical threaded tool pin profles. Similarly, the tool spinning speed and tool travel speed also varied while in FSP. Before the processing, the A356 alloy was prepared by the grooved surfaces for packing the chromium oxide particles to compose the aluminium metal matrix composites. Te tensile strength and hardness was employed to carry out from the friction stir processed A356 alloy with infuencing of Cr 2 O 3. Te maximum occurred tensile processing parameters are 1500 rpm of spinning speed, 6 mm of tool pin sizes and 90 mm/min of tool travel speed. Similarly, the maximum obtained hardness processing parameter are 2000 rpm of spinning speed, 5 mm of tool pin sizes and 90 mm/min of tool travel speed. A scanning electron microscope was utilized to investigate the dispersed Cr 2 O 3 in the A356 alloy for confrming the refnement grains in the nugget zones of FSPed A356 alloy. Te increased grain boundary by the infuence of diferent tool pin sizes was the major reason to produces the better mechanical properties in the processed A356/Cr 2 O 3 .

This paper presents basic tribological properties of A356/10SiC/1Gr hybrid composites in conditions with lubrication. Hybrid composite specimen is obtained by compocasting procedure. A356 aluminium alloy is used as a base matrix alloy, reinforced with 10wt% of SiC and 1wt% of graphite. Tribological tests are done on advanced and computer supported tribometer with block-ondisc contact pair. By the experimental plan, test is conducted under three different values of sliding speed, three different values of normal load, different sliding distances, and also different lubricants. SEM and EDS are used for wear analysis. The analysis has shown the presence of MML, which means that there was transfer of material from steel disc to composite block.

Miniaturised tensile tests coupled with in-situ scanning electron microscopy are used to deduce the grain boundary properties of a nickel-based superalloy at 750 C. This allows the damage initiation, evolution and failure processes to be observed directly. The significant variation in ductility e consistent with the limited number of grain boundaries being present e is rationalised using a crystal plasticity approach calibrated by experiments on single crystals loaded along the <001>, <011>, and <111> directions. Quantitative strength and toughness values for the grain boundaries are estimated using a cohesive zone method. The modelling approach is used to determine an approximation of the size of the representative volume element (RVE) needed for volume-averaged behaviour.

Friction stir welding (FSW) is a solid-state joining technique where the joint strength is mainly influenced by three process parameters, namely, spindle speed (N), welding speed (V), and plunge force (Fz). The modelling of complex relationships between the process parameters and joint strength requires many experiments, which is a challenging, time-consuming, and non-economical affair. To tackle this problem, computational mathematical models such as deep learning (DL) can be employed to predict the joint strength reliably. In this paper, DL techniques, namely, deep multilayer perceptron (DMLP) and long short-term memory (LSTM) networks have been proposed for such a purpose. The DL networks were first trained with the FSW experimental data and then, the pre-trained models were used for predicting the weld strength. It was found that the DMLP and LSTM models provided lower prediction errors, which are RMSE of 3.30 and 7.63, respectively, and can be effectively utilized for determining weld quality. The proposed DL-based techniques were further compared with the traditional modelsthe shallow artificial neural network (SANN) model having an RMSE of 27.11 and the ANFIS model having an RMSE of 5.31. DMLP was found to be superior in determining the weld strength most accurately.

The preparation of AA7076 hybrid composites with SiC and Graphite reinforcement by the stir casting method. Wear resistance and coefficient of friction tests of the developed composites were conducted using a Pin-on-Disk apparatus under dry sliding conditions. Micro Vickers hardness testing showed substantial hardening of the composites with the addition of SiC and Graphite. In contrast, the addition of SiC significantly reduced the wear rate. This article systematically analyzed how the effects of reinforcement percentage, sliding velocity, and applied stress will influence the wear rate and coefficient of friction. GRA was used for the optimization of parameters; further, some information was obtained about the best conditions which ensure improved wear performance.

This project is targeting the optimization of the production process of a crankshaft industry through the reduction of waste and lead time through the use of lean methodologies, specifically Value Stream Mapping (VSM). This approach was initiated with the gathering of in-depth manufacturing data from the industry, and then a current state map was created. After close examination of the map, some non-value-added activities were recognized, including redundant motions of both the components and employees, inventory accumulation, unnecessary scrap creation, and rework on components. To counteract these inefficiencies, a variety of lean tools, including Kaizen, Poka Yoke, and various quality management practices, were adopted.

Aluminium alloys are used as lightweight materials especially in the aerospace and automotive industries. They have a number of properties such as high corrosion resistance due to the surface oxide coating, low relative weight and better castability. At normal temperatures, metal oxides are more resistant than the metal itself. The oxide layer is much thinner than the metal but protects it from interacting with the air. The kinetics of oxidation processes is the subject of the current work. As the temperature rises, the oxidation process usually proceeds in the presence of water vapour, and its rate depends on various factors, including the initial oxide layer and oxidation kinetics. The values of the oxidation exponent n аrе calculated for aluminium ribbons with different contents of Fe, Mg and Sb. Their influence on the intensity and two-stage tendency of the oxidation process is established.

The development of modern nanotechnology has influenced the principles, design and characteristics of machines and parts. This applies mostly to materials that are used in the space industry. The first aspect concerns the technologies of synthesis, and the second-the qualities and applications of the materials. To date, a limited number of scientific publications describing the preparation and production of materials in space conditions have been published. This article describes the equipment used during the second Russian-Bulgarian flight. In 1988, in space, on the MIR orbital station, 3 experiments related to materials science were conducted by Bulgarian researchers. One of the experiments is "Structure" led by N. Stoichev (BAS). A multifunctional apparatus "Kristalhizator CSK-1" manufactured in Czechoslovakia was used.

Asymmetric rolling refers to the conditions wherein velocities or diametersof two work rolls are different. Compared to symmetrical rolling, asymmetric rolling is more effective on microstructure modification and texture evolution. Intense shear deformation can be introduced into asymmetric rolling to enhance the ductility and formability of aluminum alloy and this is the aim of current research. The process of the asymmetrical rolling was done on specimens with different reductions (10%,15%, and 20% reductions). Then the tensile test was conducted at room temperature at the strain rate range between 0.33×10-3s-1 -3.33×10-3s-1 to study the ductility property of the asymmetric rolling-deformed samples and also compared with as-received samples. The results show that the as-received specimen gave the highest elongation of42.7%, while the lowest elongation of 22.4% was obtained by the (20%) thickness reduction specimen. Also, the as-received sample at an initial strain rate of 3.33×10-3s-1 gives the highest tensile strength value equal to 550MPa.

Roll bonding of aluminum/magnesium laminates combines the good corrosion resistance of aluminum alloys with the beneficial mechanical properties of magnesium alloys. We studied the microstructure of aluminum Al-1051/AZ31 magnesium laminates fabricated by the roll-bonding process. The fabricated laminates were investigated in the as-fabricated condition and after subsequent stress relief annealing treatment at temperatures ranging from 200 • C to 400 • C. The investigation aims to determine the optimal temperature to decrease the residual stress of the severely deformed microstructure of the roll-bonded Al/Mg laminates. Internal residual stress can limit the application of such laminates. Such a thermal treatment enhances the interdiffusion of Al and Mg at the Al/Mg interface resulting in the formation of intermetallic phases. Intermetallic compounds are undesirable due to their brittleness and impact on the overall laminate structure and integrity. Detailed microstructure characterization of the intermetallic compounds and internal residual stress by means of recrystallization degree revealed that stress-relief treatment at 200 • C/1 h is sufficient to reduce

In recent years, researchers have conducted studies comparing the mechanical properties of
austempered ductile iron (ADI) with those of standard ductile iron, steel, forged components,
and even aluminum. ADI is frequently preferred, particularly in the automotive industry, as
well as in heavy industry and the energy sector. Its matrix features a unique ausferritic
structure consisting of needle-like ferrite (acicular ferrite) and carbon-enriched austenite
surrounding the graphite nodules. ADI offers an optimal combination of high strength,
hardness, toughness, and wear resistance. Its ability to simultaneously exhibit all these
properties has made it a subject of cost-reduction studies in many applications. Consequently,
it has become increasingly popular in engineering design over time. With the growing interest in ADI, research focusing on the effects of alloying elements on its
mechanical properties has intensified. Alloying is crucial for enhancing the hardenability of
thick-section ductile cast iron parts. Alloying elements can prevent the formation of pearlite
during austempering, maintain the presence of austenite in the structure at low temperatures,
and expand the austenite region. The spherical graphite nodules in the structure act as solid
lubricants, reducing the coefficient of friction and minimizing energy losses in moving parts.
They also prevent crack formation, thereby improving wear resistance and extending the
material's service life. As a result, ADI demonstrates excellent fatigue resistance. However,
the solid lubricant function of the graphite nodules can diminish under excessive loads, at
high temperatures, and during prolonged exposure, making it sensitive to operating
conditions. The purpose of this study is to examine recent studies investigating the effects of
alloying elements on the mechanical properties of ADI.

Aeronautical structures have been assembled for decades using a wide variety of welding and joining techniques. Over the last 15-20 years significant developments in joining techniques have occurred. Aluminium alloys have been the main traditional materials in civil aeronautical industry for the fuselage and structural parts. In order to reduce weight, improving fuel efficiency, there is the need to develop innovative solutions to join aluminium components in a single lap joint (SLJ) configuration with higher strength to weight ratio than riveting and fastening. In this work, a combination of the friction stir welding (FSW) and adhesive bonding (AB) processes is presented. Quasi-static mechanical properties, fatigue behaviour and other properties of the friction stir weld-bonding joints were assessed and compared with adhesive only and friction stir welded only joints. The development of this new joining technology, combining FSW with AB, resulting in friction stir weld-bonding, aims to incorporate properties and characteristics of both joining technologies, as well as improving damage tolerance. The present research involved the production of two types of overlap joints -FSW and hybrid friction stir weld-bonding. The main objective of this study is to compare the different joining technologies in lap joint configuration and evaluate the influence of different parameters on the mechanical behavior of the joints. The hybrid joints present higher strength, ductility and hardness, with the highest joint efficiency achieved in the hybrid joint produced with 450 kgf. These findings lead to the conclusion that -hybridization process confers a joint efficiency improvement between 20-30 % in most cases.

ND YAG laser drilling of austenitic stainless-steel material is studied here. Taguchi method with grey relational analysis to determine the laser drilling parameters with consideration of multiple quality characteristics, is studied in this paper. The effort has been made to minimize the drilling defects, such as hole taper. In present research, A pulsed ND: YAG (Neodymium-doped Yttrium Aluminum Garnet) laser which creates high intensity infrared radiation at a wavelength of 1064 nm, with output powers ranging 600W used for laser drilling of austenitic stainless steel, a material which has performed well in laboratory tests as well as in various fields of engineering and industrial, is perceived. It has wide range of applications in various fields like industrial, medical, heat engines etc. Laser drilling input factors such as lamp current, pulse frequency, air pressure and pulse width. The dimensional accuracy and quality of holes are very important for some specific applications of holes. circularity of drilled hole at entry and exit, and taper are very important attributes which influence the quality of a drilled hole in laser drilling. Using the taguchi method an L27 orthogonal array has been used for this experiment. From the grey analysis, a grey relational grade is obtained and based on this value an optimum level of drilling parameters has been identified. The result of the confirmation experiments show that optimal laser drilling parameters can be determined successfully so as to perk up numerous quality characteristics through this approach.

Purpose: The aim of the work is to present the influence of casting method and anodic treatment parameters on properties, thickness and structure of an anodic layer with (PVD) physical vapour deposition method achieved TiN layer formed on aluminum casting alloys.

The objective of this work is to investigate the affecting variables of milling process to optimize surface roughness and material removal rate during machining of 7024 Al-alloy. The machining operation is implemented on C-TEK CNC milling machine. The effects of the selected parameters on the chosen characteristics have been accomplished using Taguchi's parameter design approach; also ANOVA is used to evaluate the contribution of each parameter on the process outputs. Different feed rates are studied ranging from (60, 80 and 100) mm/min. It is found that high feed rates give a high material removal rates and good surface roughness. On the other hand, it is found that a higher spindle speeds gives better surface roughness with a little effect on material removal rate MRR. The process results showed that maximum MRR achieved (2.40) mm3/min when machining feed rate (100) mm/min, spindle speed (1000) r.p.m, and depth of cut (0.6) mm. While good surface roughness (0.41 µm) is obtained when machining feed rate was (100) mm/min, spindle speed (1000) r.p.m, and depth of cut (0.2) mm. The level of importance of the machining parameters for material removal rate and surface roughness is determined by using Taguchi designing experiments and the variance analysis (ANOVA).

Modern manufacturers, seeking to remain competitive in the market, rely on their manufacturing engineers and production personnel to quickly and effectively set up manufacturing processes for new products. Taguchi Parameter Design is a powerful and efficient method for optimizing quality and performance output of manufacturing processes, thus a powerful tool for meeting this challenge. This Paper discusses an investigation into the use of Taguchi Parameter Design for optimizing surface roughness generated by a conventional lathe. Control parameters being consider in this paper are cutting speed, feed rate and depth of cut. After experimentally turning sample workpieces using the selected orthogonal array and parameters, this study expected to produce an optimum combination of controlled parameter for the surface roughness.

In the field of linear elastic fracture mechanics, the fracture toughness is an important parameter for safe-life estimation of structural parts. The plane strain fracture toughness, KIc, is thickness independent and it can be obtained through the ASTM-E399 testing standards. The ASTM standards and procedures require detailed specimen preparation, pre-fatiguing the notch, and fatigue crack growth rate measurements. These tests are expensive and time consuming. Progressive failure analysis is therefore used to estimate material fracture toughness. This approach will combine finite element analysis (FEA) with a General Optimization Analysis (GENOA) software (1) to update material properties as damage occurs. The proposed approach will consider the static properties obtained from the stress-strain curve as an input to assess the crack tip stress and strain fields. The GENOA Progressive Failure Analysis (PFA) is based on material degradation concept throughout the FEA model as the load ...

The purpose of this work was the development of a reliable technique to evaluate the intensity of acoustic cavitation during degassing of aluminium melts and to use it to select the optimum processing time for an envisaged degassing efficiency. A high sensitivity piezoelectric disk type device was used as a sensing feedback in water and liquid AlSi9Cu3 alloy. The signal acquisition and processing was carried out on a dedicated LabVIEW ® based application which allowed real-time monitoring of the piezoelectric sensor's data and ultrasonic parameters. Standard Fast Fourier Transform was applied to obtain the dominant frequencies, as well as the sub and ultra-harmonics. It was found that the amplitude of the FFT sub-harmonic (f/2) was the best indicator to evaluate the process degassing efficiency, and it could be used to select the optimal processing time, independently of other variables. The developed methodology was applied to several AlSi9Cu3 melts, and validated by measuring the final alloy densities and the volume fraction of porosities, revealing that it is an efficient, fast and cost effective technique to evaluate the degassing treatment of aluminium alloys. Experimental curves of AlSi9Cu3 alloy degassing efficiency as a function of f/2 amplitude are presented for different degassing times.

In today's world, the need for new technologies that meet the growing market and industry demand is perceived daily. Therefore, in the area of materials engineering, the aluminum alloy stands out among the others, due to its excellent mechanical characteristics, which facilitates its application in different situations. In the present work, we start from the hypothesis that, during the solidification process of aluminum alloys, if we subject an aluminum alloy to different cooling conditions after casting, we could improve and improve its mechanical properties. For this purpose, we cast aluminum alloy Al -6061, poured and cooled with: oil, water, ambient air and compressed air. We submitted the molten samples to sanding and chemical attack and finally we evaluated their macro and microstructure. In the end, it was possible to observe in the verification of the macrographs, different morphologies and the occurrence of porosities, greater formations occurred in the sample cooled by compressed air. In the micrograph samples, all showed grain formation very different from each other. We concluded that the ingots under different cooling resulted in different morphologies and microstructures; in oil-cooled samples it was possible to identify the phases present in the alloy.

In this research, the mechanical properties (microhardness and wear) of Al-8Si-3Cu-2Zn nanocomposites with 0, 2, and 5% by weight of tungsten disulfide nanoplates have been investigated. The studied nanocomposite was produced through mechanical grinding and hot pressing at a temperature of 510 degrees Celsius. The microstructures of powders before and after mechanical grinding and sintered samples were studied through electron microscopy (SEM). By examining the worn surfaces after the wear test by electron microscope, the cause of weight loss was investigated. The results show that by adding tungsten disulfide nanoplates up to 5% by weight, the microhardness of the samples increases more than twice and from 50 Vickers for Al-8Si-3Cu-2Zn to 101 Vickers for Al-8Si.-3Cu-2Zn nanocomposite reaches -5%WS2. According to the results of the wear tests, the wear rate for Al-8Si-3Cu-2Zn-5%WS2 will decrease by 32% %, compared to the Al-8Si-3Cu-2Zn alloy background. Therefore, Al-8Si-3Cu-2Zn-5%WS2 nanocomposite can be used as a self-lubricating nanocomposite with favorable wear properties.

Industrial electroplating is a critical process in manufacturing and engineering, used to coat metal parts with a thin layer of metal to enhance their properties. This technique is essential in improving the durability, appearance, and corrosion resistance of components used in various industries, from automotive to electronics. In this article, we'll explore the electroplating process, its benefits, common applications, and answer some frequently asked questions about this versatile technique. Industrial Electroplating is the process of using an electrical current to deposit a thin layer of metal (such as gold, silver, nickel, chrome, or copper) onto the surface of a metal object. This is done by immersing the object (the cathode) into a solution containing metal ions (the electrolyte) and passing an electric current through the solution, causing the metal ions to bond with the surface of the object.

This study was aimed to investigate the weld microstructure and mechanical properties of as received and cryorolled Al 5083 alloy using friction stir welding (FSW). The comparison of the weld joint and mechanical properties of as received and cryorolled Al 5083 alloy was made. The as received Al 5083 alloy was cryorolled up to 50% reduction to produce Ultrafine grained (UFG) structure. Microstructural studies revealed severely deformed grains which are elongated along the rolling direction in cryorolling condition. Various rotational speeds (865, 1140, 1500) rpm were investigated at 2° tilt angle. Both hardness and tensile properties of as received and cryorolled Al 5083 alloy decreases with increasing rotational speed. In general, the hardness and tensile properties of cryorolled Al 5083 alloy are higher compared to as received. The highest hardness (85.2 HV) was obtained at nugget zone for cryorolled Al 5083 alloy at 865 rpm. For tensile test, the peak of yield and tensile strength was achieved by cryorolled sample at 865 rpm which recorded value of 145.61 MPa and 224.21 MPa respectively. The yield and tensile strength of cryorolled sample at 865 rpm improved about 13.36% and 1.14% than as received Al 5083 alloy. The fracture surface of the cryorolled sample after tensile test consisting of welldeveloped dimples over the entire surface which indicated fractured in ductile manner.

Dette er en elektronisk serie fra 2005 som erstatter de tidligere seriene NINA Fagrapport, NINA Oppdragsmelding og NINA Project Report. Normalt er dette NINAs rapportering til oppdragsgiver etter gjennomført forsknings-, overvåkings-eller utredningsarbeid. I tillegg vil serien favne mye av instituttets øvrige rapportering, for eksempel fra seminarer og konferanser, resultater av eget forsknings-og utredningsarbeid og litteraturstudier. NINA Rapport kan også utgis på annet språk når det er hensiktsmessig. Som navnet angir behandler temaheftene spesielle emner. Heftene utarbeides etter behov og serien favner svaert vidt; fra systematiske bestemmelsesnøkler til informasjon om viktige problemstillinger i samfunnet. NINA Temahefte gis vanligvis en populaervitenskapelig form med mer vekt på illustrasjoner enn NINA Rapport. Faktaarkene har som mål å gjøre NINAs forskningsresultater raskt og enkelt tilgjengelig for et større publikum. De sendes til presse, ideelle organisasjoner, naturforvaltningen på ulike nivå, politikere og andre spesielt interesserte. Faktaarkene gir en kort framstilling av noen av våre viktigste forskningstema.

İnsanlık, belki de var olduğu ilk günden bu yana, hep bir şeyleri merak etmiş, incelemiş ve bulduklarıyla yetinmeyip araştırmaya devam etmiştir. Hiç bitmeyen bu merak ve araştırmalar sonucu bulduklarına yenilerini eklemiş ve teknoloji kavramının ortaya çıkmasını sağlamıştır. Ekonomideki gelişimlerin başlıca temel dayanağını teknolojik yeniliklerin sunmuş olduğu fırsatlar oluşturmaktadır. Malzeme teknolojisi açısından teknolojik gelişmelerin ilk basamağını malzeme özelliklerinin incelenmesi teşkil etmekte ve bu özellikler diğer bir tabir ile davranışlar malzemelerin içyapılarından etkilenmektedir. Malzeme içyapıları imalat esnasında uygulanan ısı ve deformasyondan etkilenerek değişim gösterebildiklerinden, imalat süreci sonunda malzeme özellikleri başlangıç malzemesinden ya da tasarımda dikkate alınandan farklı olabilmektedir. Bu çalışmada, çeliklerin sıcak yığma işlemi esnasında ve sonrasında mikro yapı değişimlerine ait literatürde bulunan ve kabul edilen malzeme modelleme kriterleri incelenmiştir. Ardından 1040 çeliği üzerinde yapılan çeşitli sıcaklıklardaki sıcak yığma deneyleri sonrasında numunelerin sertlikleri, mikro yapı görünümleri incelenmiş, sonuçlar modellemeler ile karşılaştırılmış ve irdelenmiştir. Öncelikle tüm yaşamım boyunca kararlarımın doğruluğuna inanıp bana olan desteklerini hiç esirgemeyen aileme; bilgi, deneyim ve sabrı ile bana rehberlik eden danışman hocam Sayın Doç. Dr. Şafak YILMAZ' a ve varlıkları ile hayatıma anlam katan arkadaşlarım Görkem KIZILTAN, Emrah DENİZ ve Nur PEHLİVANOĞLU' na teşekkürlerimi sunarım.

Additive manufacturing (AM) AA5083 hybrid nanocomposites Molybdenum disulfide nanoparticles (MoS 2) Nano-Diamond (ND) Heat input A B S T R A C T Additive Friction Stir Deposition (AFSD) is a solid-state additive manufacturing technique that utilizes high temperature plastic deformation to produce fully dense parts, resulting in refined microstructures and robust mechanical bonds for volumetric damage repair applications. This research employs the AFSD process to fabricate AA5083-H321/2.75 % wt nano MoS 2 /diamond (ND) hybrid composite parts, alongside a noncomposite part for comparison. The primary objective was to enhance the microstructure by examining the effects of deposition parameters, including rod rotational speeds (800, 1100, and 1400 rpm) and feeding rates (5 and 12 mm/min), which affect heat input during AFSD. Evaluations of the consumable rod and deposition parts included macro-structural and microstructural analyses using OM, XRD, and SEM equipped with EDS. Additionally, hardness analysis through contour map images, surface morphology analysis of wear via SEM, and assessments of electrochemical corrosion behavior were conducted. Results demonstrated that defect-free multilayer AA5083-MoS 2 /ND nanocomposites with well-bonded layers, uniform MoS 2 /ND distribution, a low diameter/height (D/H) ratio, fragmented intermetallic compounds, and refined grain structures were successfully produced. The AFSD process composites exhibited superior properties, including lower corrosion rates, increased hardness, and enhanced wear resistance, compared to the AA5083 consumable rod and non-composite part. Notably, the composite part C800-5, produced under optimized parameters (800 rpm, 5 mm/min), achieved a 90 %-40.55 % grain size reduction, a 21.23 %-14.74 % hardness increase, a 23.02 %-8.15 % decrease in wear rate, and a 90.45 %-88.66 % reduction in corrosion rate compared to the AA5083 consumable rod and noncomposite part, respectively.

The integration of Computational Fluid Dynamics (CFD), Machine Learning (ML), and additive manufacturing techniques has revolutionized the Laser Powder Bed Fusion (LPBF) process by enabling predictive modeling, process optimization, and quality control. This study explores the synergy between CFD simulations and ML algorithms to predict microstructural outcomes, such as grain size and porosity, based on process parameters like laser power, scan speed, and particle size. The proposed hybrid framework leverages CFD to generate synthetic datasets, which are then utilized to train ML models, including Random Forest Regression. These models accurately capture the non-linear relationships between process parameters and microstructural properties. The results underscore the potential of this approach for enhancing process efficiency, reducing computational costs, and minimizing experimental trials. Key findings reveal that energy density significantly influences microstructural outcomes, with higher densities reducing porosity and refining grain structures. Furthermore, the study highlights real-time process control and optimization opportunities through ML-driven predictions. By combining the physical rigor of CFD with the adaptability of ML, this framework provides a pathway toward intelligent manufacturing systems capable of delivering high-performance components with tailored properties. Future research should incorporate experimental data and advanced ML techniques to enhance reliability and generalization.

Nanocomposites nowadays, have the tendency to replace conventional composite materials in many commercial products. These composites find application in a diverse range of fields, including computer components, data storage systems, various membranes and filters, as well as advanced materials in the automotive and aerospace industries. They are available in different forms and from various manufacturers, providing a wide selection. Although they may be more expensive, compared to conventional materials, the ability to customize the properties of nanocomposites to the specific needs of end-users makes them highly attractive and innovative. International scientific bodies, including International Standards Organization (ISO), are actively working on formulating standards to regulate the safe use, disposal and recycling of nanowaste. The importance of standardization will grow with the expansion of the market for metal matrix nanocomposites. The aim of this paper is to review the existing research on metal matrix nanocomposites and their application to achieve significant improvements in the chemical, aerospace, automotive and other industries.

W.M. Thomas at The Welding Institute of UK in 1991 invented friction stir welding for the welding of aluminium alloys and as time progress use of light weight material and others which were difficult to weld by other conventional method increasing continuously in the field of aerospace, shipbuilding and marine, robotics and computers and other industries which motivated researchers for development and progress in friction stir welding. Friction stir welding method involve a non consumable tool with specially designed pin and shoulder is rotating and inserted into the faying surfaces and traverse along the line of joint, by this adiabatic shearing and mechanical mixing welded the material. In friction stir welding material is heated at elevated temperature of the base material for which heat generation is an important factor. Less heat reduces the rheology and mixing of material whereas more heat reduces the strength of the welded material. This research is for obtain the suitable te...

Microstructure evolution over a wide range of growth rates has been examined in the Al-Sm system in which different microstructure selection, from eutectic to dendritic to amorphous material, with increasing growth rate can occur. Experiments were carried out for compositions between 11 and 25 wt.% Sm and the velocity was varied from 2x10 -4 to 635 mm/s. Low velocity studies were carried out using the Bridgman technique, whereas high velocity studies were carried by using the laser scanning technique. The maximum velocity for eutectic growth was determined, and the results were compared with the theoretical predictions. A transition from eutectic to α-Al dendrites was observed when the eutectic became unstable, and a coupled zone boundary on the Al side was determined. The present results were compared with those in the Al-Cu alloys, and the velocity at which the eutectic becomes unstable was found to be an order of magnitude smaller, which is related to the higher activation energy for diffusion in the Al-Sm system.

Research on ultrasonic treatment (UST) of aluminium, magnesium and zinc undertaken by the authors and their collaborators was stimulated by renewed interest internationally in this technology and the establishment of the ExoMet program of which The University of Queensland (UQ) was a partner. The direction for our research was driven by a desire to understand the UST parameters that need to be controlled to achieve a fine equiaxed grain structure throughout a casting. Previous work highlighted that increasing the growth restriction factor Q can lead to significant refinement when UST is applied. We extended this approach to using the Interdependence model as a framework for identifying some of the factors (e.g., solute and temperature gradient) that could be optimised in order to achieve the best refinement from UST for a range of alloy compositions. This work confirmed established knowledge on the benefits of both liquid-only treatment and the additional refinement when UST is applied during the nucleation stage of solidification. The importance of acoustic streaming, treatment time and settling of grains were revealed as critical factors in achieving a fully equiaxed structure. The Interdependence model also explained the limit to refinement obtained when nanoparticle composites are treated. This overview presents the key results and mechanisms arising from our research and considers directions for future research.

This major-project investigates the impact of welding current variations on the tensile properties of SMAW welded
joints in mild steel. The study aimed to discern how changes in welding current affect the mechanical characteristics
of the welded joints, specifically focusing on tensile strength, yield strength, and elongation. The effect of welding
current on welding speed and hardness of heat effected zone. The test specimen was then grinded and hardness of each
specimen was measured at three points i.e., parent metal, HAZ and weld metal by using Brinell Hardness Tester. Liquid
Penetration Test is done to find the defects. Tensile test is done to find the Highest Tensile Strength of the specimen
which, it can withstand.

Magnesium alloys can be used for lots of sectors with its suitable characteristics especially preferred for automotive and aerospace industry because of its light weight properties. This material is slight just like the polymers but also exhibits a unique strength feature as the other metals. High pressure die casting of magnesium alloys has been the fastest grown up and the most globally developed section of the magnesium industry. Besides, in die casting industry the cold chamber process has been favored for its unique ability to transform the injected molten magnesium into an accurately dimensioned form in the shortest possible cycle time. Although high pressure die casting is a very precision process; there are lots of factors which are effective on the product quality and mechanical properties. The process parameters; casting and die temperatures, filling time, plunger and gate velocities, injection and intensification pressures, spearhead of these factors. This paper investigates the present works about the effects of process parameters on the product quality in literature. For obtain qualified casting products which have good mechanical properties and low porosity contents; the casting process should be made under high injection and intensification pressures, with low casting and high die temperatures and with minimum flow velocities.

The evolution of microstructure affect from different pouring temperatures and holding times using a direct thermal method is presented in this paper. The direct thermal method is one of the thermal techniques which are used to produce semi-solid metal feedstock. In this experimental work, aluminium 7075 alloy was used. The experiments were carried out by processing a sample with a 0.7 °C/s cooling rate to evaluate the formation of the microstructure. In direct thermal method experiment, a molten 7075 was poured into a cylindrical copper mould at different pouring temperatures of 680 °C and 660 °C meanwhile the holding time of 20 s, 40 s and 60 s before quenched into room temperature water. The sample processed by the cooling rate of 0.7 °C/s produced a large microstructure. The formation of a spheroidal microstructure was obtained with the combination of a suitable pouring temperature and holding time. The pouring temperature of 665 °C and the holding time of 60 s produced a finer ...

The direct thermal method is used for the creation of globular microstructures suitable for semi-solid metal forming. In this paper both simulation and experimental results using direct thermal method are presented. ProCAST® software was used to estimate temperature distribution inside the aluminium billet. In validation work, molten aluminium A356 was poured into metallic copper tube moulds and cooled down to the semi-solid temperature before being quenched in water at room temperature. The effect of pouring temperatures of 630°C, 650°C, 665°C, 680°C and holding times of 45s and 60s on the microstructure of aluminium A356 alloy were investigated. The simulation results showed that the average temperature rate within the copper mould, from initial pouring temperature to just before quenching, was approximately 1°C/s. Examination of the solidified microstructures showed that the microstructure was more spherical when lower pouring temperatures and holding periods were used. From the micrographs it was found that the most globular and smallest structures were achieved at processing parameters of 630°C and 45s.

The idea of the final work is to show the production and technology preparation of the production required for casting the lock valve housing under the trade name "HAWLE BAIO COMBI III DN200 GEHAUSE". The type of material from which the casting will be cast is also described in detail. The process of developing the documentation and tools required for casting and finding an adequate technological solution for the pouring system to obtain the correct casting, as well as the part of production, molding, is presented. This work describes the complete process of obtaining a finished cast according to customer requirements. The results and reasons for using these technologies are described in chapters of the final work.

Se han investigado los efectos de un pretratamiento superficial empleado en el sector aeroespacial sobre la aleación 2024-T3 Al-Cu antes de la generación de recubrimientos por conversión química. Estos pretratamientos influyen en las fases metálicas, que desempeñan un papel clave en el desarrollo de nuevos recubrimientos de conversión sin cromo y en la susceptibilidad a la corrosión localizada en medios que contienen cloruros. El pretratamiento estudiado consta de dos etapas alcalinas y una ácida. La microscopía electrónica de barrido reveló que después del proceso completo, las fases Al(Cu,Mg) se eliminaban parcial o totalmente mediante desaleación y su posterior enriquecimiento de cobre, mientras que solo se atacó la matriz de aluminio que rodeaba las fases Al(Cu,Fe,Mn,Si). El análisis electroquímico reveló el viraje a catódico de las fases Al(Cu,Mg) que aún permanecen en la superficie mientras que la fases Al(Cu,Fe,Mn,Si) presentaron un mayor potencial de corrosión que la matriz ...

This study experimentally evaluated the forming limit diagram (FLD) of Al/Cu bimetallic sheets fabricated using explosive welding in multi-point forming. The results showed that the forming limit was greater in multi-point forming than in the Nakazima test. It was also experimentally found that the forming limit was greater when copper was the lower layer in both multi-point forming and the Nakazima test. The experimental and theoretical results were in good agreement, with an error below 10%. Dimensional optimization was performed on the pin for multi-point forming, and the optimal pin size to maximize the forming limit was 12 mm in the presence and absence of the polyurethane layer. A rise in polyurethane hardness and thickness increased the forming limit, regardless of the pin size; however, the increase rate of the forming limit was falling at pin sizes of 10 and 12 mm and growing at pin sizes of 8 and 15 mm.

Aluminum-magnesium alloys are ideal for a number of structural applications; however, alloys with magnesium content more than 3 wt% can become sensitized and susceptible to environmentally-assisted failure after exposure to moderately elevated temperatures for sufficient periods of time. Commercial Al-Mg alloys were tested in the as-received and sensitized conditions to investigate susceptibility to environmentally-enhanced cracking in fatigue crack growth. Slow strain rate testing (SSRT) of short-transverse (S-T) smooth tensile samples and fatigue crack growth testing of SEN bend specimens was also conducted in various loading orientations (L-T, L-S, S-L and S-T). Sensitization treatments included exposure to temperatures ranging from 60°C -175°C for times ranging from 10 hours to 20,000 hours. Under specific loading conditions and the presence of a local hydrogen source, IGSCC manifested itself as ST and SL splits during the cyclic loading of sufficiently sensitized L-S and L-T test specimens. The regimes of grain boundary cracking have been determined. Initial findings using ESBD data is suggestive that the high angle grain boundaries most likely to suffer IGSCC are those with a sharp gradient in the Taylor factor. Remediation treatments were also conducted on sensitized Al-Mg alloys in an attempt to reverse sensitization and restore alloy properties. While thermal re-mediation was somewhat effective in reducing the environmentally-sensitive fracture, this condition occurred at the expense of a loss in strength and its long-term effectiveness remains questionable. SEM and EBSD were used to document the locus and orientation-dependence of grain boundary failure while TEM was used to determine species present at grain boundaries susceptible to environmentally-enhanced fracture. SSRT testing of S-T samples in various environments revealed different degrees of embrittlement depending on the environment and degree of sensitization. A change in alloy sensitization kinetics occurs at around 100°C.

Fatigue crack growth experiments were conducted in humid air (RH~45%) at 25 °C on 29-mm-thick plate samples of an aluminium-magnesium (Al-Mg) 5083-H131 alloy in the long transverse (LT) direction. Samples were tested in both the as-received condition and after sensitization at 175 °C for 100 h. Delamination along some grain boundaries was observed in the short transverse plane after fatigue testing of the sensitized material, depending upon the level of ΔK and K max . Orientation microscopy using electron backscattering diffraction and chemical analyses using transmission electron microscopy and energy dispersive spectroscopy of grain boundaries revealed that Mg segregation and the orientation of grains had key roles in the observed grain boundary delamination of the sensitized material.