Soldering plays a crucial role in the electronics industry, driving the need for constant improvements in physical and mechanical properties and the management of intermetallic compound formation. Research in composite materials aims to achieve a uniform distribution of reinforcing particles within solder matrix to enhance their performance. This study investigates the integration of cobalt microparticles into SAC0307 lead-free soft solder alloy using the accumulative ROLL BONDING (ARB) method. Microstructural analysis confirmed a homogeneous dispersion of cobalt particles within the solder after three ARB passes. Moreover, increasing cobalt content led to a reduction in the size of Cu6Sn5 intermetallic compounds, from 9 µm to 5 µm with 1% cobalt by weight. Examination of β-Sn grain morphology revealed the impact of cobalt particles on recovery and recrystallization kinetics in the solder. Mechanical testing indicated a 20% decrease in interlayer strength within composite solder sheets. Tensile tests showed a 28% increase in strength and a 31% decrease in elongation for composite solder alloy containing 1% cobalt. Differential scanning calorimetry (DSC) results revealed minimal change in the melting temperature of composite solder foil.

Layered alloys and composite materials have become an increasingly popular in industrial development. The ROLL BONDING (RB) process, as a solid phase method of BONDING, has been widely used in manufacturing large layered strips. In this study, aluminum alloy (AA 5083) strips were ROLL bonded at warm and cold temperatures. The effects of the ROLLing parameters such as the amount of plastic deformation by ROLLing and ROLLing temperature that create successful bonds on the bond strength and the threshold deformation between two layer strips of AA 5083/ AA 5083 were investigated. The bond strength was evaluated by the peeling test. It was found that by increasing the ROLLing temperature or thickness reduction, the peel strengths of the bonds increased and successful bonds with higher strength were created. Also, the threshold thickness reduction decreased with increasing the ROLLing temperature. Moreover, the interfaces of laminates were studied by scanning electron microscopy (SEM) in order to investigate the BONDING quality.

An Al/Stainless Steel/Al lamellar composite was produced by ROLL BONDING of the starting sheets at 400 °C. Afterward, the ROLL bonded sheet was cut in half and the accumulative ROLL BONDING (ARB) process at room temperature was applied seven times. As a result, the central steel layer fractured and distributed in the Al matrix among different layers introduced by the repetition of ROLL BONDING process. The tensile results showed that the ROLL bonded sheet has much higher strength and strength to weight ratio compared with the initial aluminum sheet as a result of the presence of continuous steel core. However, poor ductility properties were observed during tensile test, which were ascribed to the increasing deformation resistance and localized thinning of the central stainless steel sheet during the ROLL BONDING process. The ARBed sample exhibited lower strength compared with the ROLL bonded sheet due to the breakup of stainless steel layer into many small segments. Anyway, an ultrafine grained microstructure with average grain size of 400 nm in the aluminum matrix and 71% strain-induced martensite in the steel segments were detected by the electron backscattered diffraction (EBSD) technique, which were found to be responsible for the enhancement of mechanical properties compared with the initial aluminum sheet.

The cold ROLL BONDING (CRB) is a type of BONDING process between similar and/or dissimilar metals that is bonded through plastic deformation via ROLLing process at room temperature. In addition, the accumulative ROLL BONDING (ARB) process is considered as one of the methods for applying severe plastic deformation (SPD) with the ability to achieve ultra-fine grains (UFG) structure and improved mechanical properties. In this research, a combined method was suggested consisting of ARB and CRB processes in order to fabricate UFG copper strip with simultaneous increase of strength and electrical conductivity. Microstructure, mechanical properties, and electrical conductivity of copper specimen fabricated via combined method and ARB processes were investigated. Field emission scanning electron microscope (FESEM) micrographs showed in the crystalline structure of the specimen fabricated via combined method, a large amount of the UFG with uniform distribution are observable. Also tensile strength and hardness of strips increased with increasing the number of ROLLing passes. Finally, investigation the electrical conductivity of the specimens by four-point probes test showed electrical conductivity decreases with increasing the number of ARB cycles, while the specimen fabricated via combined method increased simultaneously strength, hardness, and high electrical conductivity.

Cladding of steel with titanium alloys to improve corrosion behavior and to reduce production costs, is used widely in aerospace, chemical, nuclear and biomaterials industries. ROLL BONDING is one of the solid state processes to produce this combination. In this research the high quality BONDING of hot ROLL BONDING of titanium on steel substrate was investigated in terms of physical and mechanical properties, and the effect of nickel interlayer to prevent inter diffusion was evaluated. The microstructure at interface was observed by an optical and scanning electron microscope and the presence of intermetallic phases in the reaction zone was examined by X-ray diffraction on surfaces of the joints. The experimental results showed that the no reaction layer will be formed at the interface of steel with nickel but The interface between titanium alloy and nickel consists of the several diffusion layers include the intermetallic compounds of TiNi3, TiNi, Ti2Ni and their mixture so that the total thickness of intermetallic layers at the interface between titanium and nickel and the hardness of ROLL bonded joints increases with the BONDING temperature.

Cold ROLL BONDING (CRB) is a solid state welding process, where the BONDING is established by compressive plastic deformation of the metals. This process is applicable for a large number of materials. In addition, materials that cannot be bonded by traditional fusion-based processesmight be bonded by CRB process. In this research, cold ROLL welding of brass and IF steel was studied. The effects of process parameters such as reduction of thickness, pre-ROLLing annealing conditions and surface roughness on the mechanical propertiesof welded strips were investigated. The peeling and shear punch testswere used to investigate the mechanical properties of welded samples. It was observed that the bond and shear strengths were enhanced by increasing the reduction and surface roughness. Also, annealing treatment before the CRB process increased the bond strength and decreased the shear strength. Finally, optical and scanning electron microscopes were used to evaluate the fracture surfaces of the tensile and peelingtest specimens.

The strength of aluminum Al5083 laminated composite in accumulative ROLL BONDING (ARB) is increased using Al2O3 nanoparticles. For this purpose, the ARB process was conducted at room temperature without lubricants in four consecutive passes. A thickness reduction of 50% in each pass was considered with no heat treatment between sequential passes. In each pass, Al2O3 nanoparticles were placed between the layers. Finally, the produced metal composite was evaluated for microstructural and mechanical properties using optical microscopy, and uniaxial tensile, microhardness, and peeling tests according to the relevant standards. The primary objective of this research was to enhance the tensile strength of the composite after work hardening by incorporating nanoparticles and annealing in the final cycle. The results showed that with an increase in accumulative ROLL BONDING cycles, tensile strength and hardness increased, and this increase occurred more prominently in the initial cycles. Furthermore, the amount of elongation decreased at the end of the first pass and then increased until the end of the fourth pass. These changes in mechanical properties during the ARB process are due to the dominant mechanisms of work hardening and strain hardening in the initial cycles and the improvement in microstructure and refinement of grains in the final cycles of this process. The highest tensile strength and microhardness, which increased by 48.1% and 55.9%, respectively, compared to the initial sample were measured at the end of the fourth cycle. Additionally, comparing the heat-treated sample with Al2O3 nanoparticles to the base metal showed a 34.9% increase in strength and a 30.8% decrease in elongation.

One of the most important factors affecting the mechanical, physical and chemical properties of metals, are crystal structure and grain size. Ultrafine metals with an average grain size of 1000-100nm and nanostructured metals have an average grain size of less than 100nm. Ultrafine and nanostructured materials are known as a new generation of metal products, which have remarkably mechanical and physical properties in comparison to coarse-grained metals. In the last two decades, due to good properties such as high strength, high ductility and toughness, good corrosion resistance and high superplasticity properties, these materials have been considered by many researchers. In recent years, many methods have been proposed for severe plastic deformation and are now being developed and expanded. In these processes, in spite of the high hydrostatic pressure and the unaltered dimensions of the sample during the process, it is possible to apply very high strains, which results in the desired mechanical properties and ultrafine grained and nanostructured materials. The accumulative ROLL BONDING process is one of the methods of SPD. ARB process is simple, extensive use, low-cost, industrially capability method that can produce ultrafine and nanostructured metals. In this research, light metals such as aluminum, magnesium and titanium and also extremely used metal such as copper and steel are discussed. Also, mechanical properties, fractography and microstructural properties of ultrafine and nanostructured metals produced by ARB are compared with initial samples and the mechanisms governing of ARB process that cause changes in mechanical and microstructural properties are analyzed.

This article describes a study of the application of a ROLL BONDING technique to MS90(CuZn10) alloy strips and steel sheets using a chromized interlayer. It was found that the overall bond between these two metals resulted from two different types of bonds: a block bond, linking the MS90 alloy strips and chromium topcoat layer, and a blank bond, linking the MS90 alloy strips and bare steel surface in the area where the chromium coating has been fragmented. This study investigated the effects of plating time on the thickness of the coating layers and of the area fraction of the blank bond on the bond strength. The overall bond strength depends mainly on the strength and the area fraction of the blank bond. A linear relationship model exists between the overall bond strength and the area fraction of the blank bond. The bond strength of the blank bond was eight times greater than that of the block bond. The area fraction of the blank bond increased with increasing the coating thickness up to 55 µm, but thereafter decreased due to the rotation of the chromium blocks.

A commercial Al-Mg-Si alloy (AA 6061) was deformed by using the accumulative ROLL BONDING (ARB) process for up to five cycles at ambient temperature. The evolution of texture in this process was studied by the X-ray diffraction (XRD) method. Experimental results indicate that the combination of the shear texture composed of Rotated cube {001}<110> component and the ROLLing textures that included Copper {112}<111> and Dillamore {4, 4, 11}<11, 11, 8> components developed after the first cycle. During the first cycle, the shear texture was developed as a result of shear deformation induced by high level of friction between the ROLLs and the sheet. By increasing the number of cycles, the shear texture strength diminished and changed to the ROLLing texture. After the fifth cycle, a remarkable increase in the ROLLing texture intensity was observed due to homogenous deformation induced by the presence of fine non-shearable particles. Additionally, the presence of magnesium in solid solution influenced the texture evolution during ARB.