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Al/Mg/Al composite plates were fabricated by hot pressed sintering (HPS) and hot rolling. The main purpose of this study is to understand the effect of rolling on the microstructure, interface and mechanical properties of HPS Al/Mg/Al composite plates. Rolling can increase the compactness of the microstructure by improving the distribution of internal voids and promote the diffusion of interfacial elements, forming a transition layer consisting of phases $\beta$-Al₃Mg₂ and $\gamma$-Al${}_{12}$Mg${}_{17}$, which improves the strength, plasticity, interfacial bonding strength and interfacial deformation compatibility of the HPS Al/Mg/Al composite plates. The bending strength, tensile strength and elongation of HPS Al/Mg/Al composite plates after rolling are 520 MPa, 300 MPa and 17%, respectively. The fracture mode changes from brittle intergranular fracture to ductile dimple.

Hot stamping parts have been widely used as re-enforcement for better crash safety and other attributes as well as in lightweight applications such as vehicle B-pillar, rocker and other structure parts. In this paper hot stamped torsion beam is studied as a function of product DVP and hot stamping process. Although hot-stamping process is fairly understood, the lightweight designed torsion beam’s property as a function of various parameters is not well studied. In order to study the temperature field, stress field, strain field, thinning rate and phase distribution in the hot forming process of torsion beam, the finite element software was used in this paper. The study found the maximum principal strained area appeared in the highest temperature region due to the different regions of part contact with the tool in the different order while the maximum principal stress area is located in the lower temperature region. In the process of hot forming, the slow cooling rate of the part is 77 °C/s, which is greater than critical cooling rate of martensitic transformation 30 °C/s; With the increase of the initial temperature of sheet metal, the maximum content of austenite and thinning rate of the parts increase, and the forming quality of the parts decreases; with the increase of stamping speed, the thinning rate of parts is violent fluctuation. When the stamping speed is too large, parts of the temperature of parts is greater than the martensite transformation temperature in some regions at the end of forming; with the increase of friction coefficient, the thinning rate and the minimum content of martensite firstly increase and then decrease; the maximum content of austenite decreases first and then increases. Research shows that: when the initial temperature of blank is 850, stamping speed is 75 mm/s, coefficient of friction is 0.45, the quality of the parts is the best and thinning rate is 5.804 %. At the end of forming, the minimum temperature of parts is 285 °C; minimum martensite content is 75.63 % and the maximum content of austenite is 24.36 %.