MODELING OF AUSTENITIC GRAIN GROWTH OF 21-4N STEEL.

The effect of grain growth on 21-4N heat resistant steel was studied by static grain growth test. The experimental results show that the temperature inhibits carbide grain growth is between 1 000 - 1 120 °C. When heat preservation time is over 40 min, the driving force of grain boundary is balanced with binding force of carbide nail, grain size will not grow up. There is no limit of grain size due to no pinning effect of carbides when the temperature is above 1 180 °C. Based on the theory of grain boundary migration, the grain growth model of 21-4N heat-resistant steel was established, and the relationship between the average grain size and the time of heat preservation at different temperatures was predicted. [ABSTRACT FROM AUTHOR]