Deformation heating consideration when selecting temperature-speed modes of deformation for AMG6 alloy

The article presents the results of numerical and laboratory experiments on open-die forging of 20 mm diameter workpieces from a heating temperature of 20, 130, 260 and 390 °C. Simulation has shown that during cold open-die forging, the deformation heating can reach 90 °C, and during open-die forging from a temperature of 130 °C - 70 °C, which must be taken into account when selecting the temperature and speed conditions of deformation. During hot open-die forging (heating up to 260 °C), the deformation heating can reach 20-40 °C, which can be critical in terms of overburning and loss of plastic properties and corrosion resistance of finished products. Laboratory experimental studies on open-die forging of workpieces heated to 20, 130 and 260 °C revealed better plasticity and deformability of the AMg6 alloy when heated to 130 °C. Metallographic analysis of deformed samples revealed that when heated to 260 °C, the microstructure of the AMg6 grain undergoes recrystallization. Along with the recrystallized grains, traces of overburning are observed in the structure. Along the grain boundaries, the pores form a virtually continuous network of intermetallic phases. Open-die forging of AMg6 alloy samples heated to130 °C ensured preservation of the deformation texture and hardening from 86 to 133 HV1, while completely eliminating the formation of both external and internal cracks, pores and any signs of destruction. The deformation behavior of the AMg6 alloy at a heating temperature of the workpiece up to 130 °C, revealed in this study, indicates the prospects for conducting additional research on the study of changes in the microstructure and mechanical properties of this alloy during warm deformation.