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In this article, the compression simulation of AZ31 magnesium alloy is simulated by the molecular dynamics method. The effects of loading mode, temperature, and strain rate on the compression behavior are analyzed. The lattice distortion, mechanical behavior, structural evolution, and dislocation evolution in the compression process are deeply analyzed, and the results of different loading modes are obtained. The hexagonal close-packed (HCP) → face-centered cubic (FCC) phase transformation mechanism of AZ31 magnesium alloy during compression at temperature and strain rate, which is related to the mechanical behavior, has been studied completely. This article perfects the research on the compression behavior of magnesium alloys, excavates the application potential of magnesium alloys, and provides a new idea for improving the processing technology and developing high-performance magnesium alloys.

316 L N L-shape stainless steel is used in ITER Side Correction Coil (SCC) box. Finite Element Method (FEM) simulation is adopted to analyze metal flow characteristics, forecast extrusion force and ascertain extruder tonnage of 316 L N L-shape stainless steel during extrusion process. Based on simulation results, 316 L N round forged billet is used to manufacture L-shape stainless steel by extrusion process. The extrusion process includes circular furnace preheating, induction heating, glass lubrication, mould design and deformation design. 316 L N L-shape stainless steel is manufactured by Φ360 mm circular container and 60 MN horizontal extruder successfully. Mechanical properties and microstructure of 316 L N L-shape stainless steel all accord with the requirements of ITER SCC box. SCC box case is manufactured by bending, machining and welding processes. X-ray, ultrasonic testing (UT) and penetration testing (PT) are used to inspect the welding quality of SCC box case. The SCC box case passes the acceptance of ITER project expert group, this result verifies that the extrusion process and manufacture process are reasonable and feasible.

Hot deformation behavior of Incoloye028 alloy was investigated by conducting hot compression tests on Gleeble-3800 simulator in the temperature range of 1223–1473 K and the strain rate range of 0.1–50 s−1. True stress–true strain curves showed that the flow stress increases with the decrease of deformation temperature and the increase of strain rate. The constitutive equations of Incoloy028 alloy were obtained by introducing Zener–Hollomom parameter, the flow behavior can be described by the hyperbolic sine function and the activation energy changes with strain rate and temperature significantly. The hot working maps of Incoloy028 alloy were proposed on basis of dynamic materials model. The hot working maps for different strains indicated that there were two instability zones, one zone is in the temperatures range of 1423–1473 K and strain rate range of 0.1–50 s−1, and another zone is in the temperature range of 1223–1423 K and strain rate range of 0.6–1 s−1. The reasonable hot working temperature range is 1423–1473 K when strain rate is more than 50 s−1.

304L H-shaped stainless steel is used as the support frame of the passive residual heat removal heat exchanger (PRHR HX) in a nuclear fission reactor. The extrusion process is adopted to manufacture the 304L H-shaped stainless steel. Finite element method simulation is herein used to analyze metal flow characteristics, optimize the extrusion die, and predict the extrusion force at different temperatures and speeds. A Φ400-mm container and Φ388-mm forging billet are selected, and the 304L H-shaped stainless steel is successfully manufactured using a Germany SMS 60 MN horizontal extruder. The mechanical properties and microstructure of the manufactured 304L H-shaped stainless steel meet the requirements of the PRHR HX, and the surfaces of the product pass the dye penetration test. The H-shaped stainless steels are used in Haiyang nuclear power plant in Shandong Province.