Compound casting refers to a process that used to produce bimetals. This study investigates the interface of Mo40/C93200 that is produced by compound casting process. In this research, molten bronze is poured around steel core, interaction between liquid and solid creates a diffusion zone and followed by a transition layer which leads to the creation of diffused region between the interfaces of metal layers. The results of micro-hardness and macro hardness used to complete the studies. The results of the hardness of the Mo40 alloy revealed that the micro-hardness of the alloy was almost 308 Vickers which this amount of hardness confirms the ferrite-pearlite state of microstructures. The results of metallography revealed that the boundary between steel and bronze alloys due to the difference in electric potential during etching evolved a galvanic cell and one section formed as the cathode and the other section as the anode. In this situation steel was corroding and bronze was protecting. As well as, the results of SEM show that the boundaries between two alloys have an acceptable adhesion and the strength of interface is sufficient. The result of tensile test indicates that the final yield strength was about 800 MPa and the elongation increases by 2%, which is an acceptable value. It is also observed that the failure is a soft defect type and a sufficient connection between steel and bronze is formed. Manuscript profile

In recent years, processes known as severe plastic deformation (SPD) have been devised to create fine-grained materials. Among these processes, equal channel angular pressing (ECAP) has been more favored than other methods due to its high efficiency, simplicity, and industrial production potential. This study aimed to investigate the sample temperature gradient during the ECAP process. For this purpose, a Taguchi experiment with influencing factors on AA2017 alloy was designed and a relationship was obtained to predict sample surface temperature. Experiments were carried out using grease, graphite powder, and MoS2 lubricants, along with routes A, BC, BA, and C. The surface temperature of the sample was measured using a laser thermometer. A finite element model was compared with the experimental conditions, and the simulation and experimental results of surface temperature were verified with an error of about 1.9%. In experiments, it was found that speed and lubricant had a significant effect on sample temperature during the process. The simulation results showed that decreasing the die angle resulted in a significant increase in temperature. Following the validation of the FEM model, the temperature gradient and distribution in the middle of the sample, wherein practical experiments could not be measured, were also investigated. Manuscript profile

Nowadays, the role of light weight materials has grown up in important industries such as aerospace and biomechanics, but before the appliance, their strength should be increased. A modern way to increase this factor along with the lightweight factoris using bimetal sheets, hence, the design of multilayer sheets has been very much considered recently. In this study, explosive welded Cu/St/Cu multilayer sheets were used in the incremental forming process to determine the springback phenomenon on different layers. The results indicated that rotational speed, feeding rate, and vertical step parameters can affect spring back in single point incremental forming process (SPIF).Three levels of vertical step size, tool rotational speed, and feed rate have been considered as the input process parameters and spring back as the output.In order to design a better experiment and analyze the data, the Taguchi method was selected on the basis of DOEin Mini-Tab software andthe results have been analyzed by two states. In the first state,the value which was closest to the nominal value is considered to be the optimal result which obtained for spring back angles with parameters of 0.75 mm for the vertical step down, 200 rpm for the rotational speed and 500 and 1000 mm/min for the feeding rate. In the second state, the least amount is considered as the optimal result in which the values of 0.5 and 1 mm of the vertical step down, 150 and 100 rpm of the rotational speed, and 1500 and 500 mm/min of the feeding rate formed the optimal outcome. Manuscript profile

Equal channel angular rolling (ECAR) process is one of the severe plastic deformation (SPD) methods that have been used to make ultra-fine grain (UFG) materials with improving the mechanical properties of samples. After performing the process at several paths, a large strain is applied to the material that can cause decreasing the grain size and improving the mechanical and physical properties of the metal. In this paper, the effects of annealing thermal treatment at various temperatures and times on the weld bond of bimetal explosive welded stainless steel-copper sheet during the equal channel angular rolling process have been investigated. For this purpose, after performing the ECAR process and thermal treatment on bimetal sheet, hardness and welding interface were studied. The results showed that performing thermal treatment at different temperatures caused the formation of intermetallic compounds in the weld bond, which would change the hardness of this region. Also, increasing the annealing time increased the thickness of the weld bond. Manuscript profile