Research on the Effective Rules for the Impact Toughness and Hardness of Austempered Ductile Iron (ADI) by Austempering Parameters

With the common engineering-purpose ductile iron used as research subject, the research on rules of austempering parameters to influence the impact toughness and hardness of austempered ductile iron (ADI) was implemented in this paper by adopting the combination of theoretical, experimental and numerical simulation methods, and setting series of austempering parameters; After the impact tests and hardness tests simulated by the finite element software - ANSYS Workbench, the simulation data were analyzed by comparing with the experimental data. The experimental results showed that: austenitizing time was longer, ADI hardness was smaller while impact toughness remained unchanged; hardness was in linearly-decreasing trend with rise of austempering temperature, while impact toughness first increased and then decreased as the austempering temperature rose, with the maximum at the temperature 350°C; The effect of austempering time on the impact toughness was very few; extension of austempering time allows the hardness to increase slightly, but only a little.