Study on Dynamic Mechanical Properties and Numerical Simulation of B610 Steel for Automotive Frame

Abstract:

With the increase of the number of automobiles and its widespread use, the modern automobile industry has put forward higher requirements for the mechanical properties of materials. In this paper, quasi-static and dynamic compression tests of B610 steel used in a truck frame have been carried out at different temperatures. It is found that the temperature softening effect of B610 steel is the most obvious in the high temperature region (400℃-600℃) under quasi-static loadings, and the strain rate hardening effect is the most obvious in the low temperature region (-80℃-25℃) under dynamic loadings. The Johnson-Cook constitutive model of B610 steel considering temperature and strain rate is obtained by fitting the test data. The numerical simulation of front collision of B610 steel truck frame is carried out. It is found that the internal energy conversion calculated by Johnson-Cook model is 92.8%, while that of linear elasticity is only 21.4%, and the peak value of equivalent stress is also reduced by 47%. This fully explains the importance of considering the temperature softened effect and strain rate strengthening effect of materials in the study of vehicle passive safety.

Key words:B610 steel, temperature;soften effect, strain;rate hardening;effect, vehicle;passive safety, front;collision of;truck frame