Dynamic Mechanical Behavior and Constitutive Model of B250P1 Low Alloy Steel

Quasi-static and dynamic tensile tests were conducted to B250P1 low alloy steel sheet at room temperature with strain rate range of 0.003-600 s-1. The effect of strain rate on the dynamic mechanical behavior of the steel was studied, and its constitutive model was established. The results indicate that the yield strength, tensile strength and flow stress of the B250P1 low alloy steel all increased with the increase of strain rate, and the strain rate effect was obviously performed. The constitutive model parameter determination method for B250P1 low alloy steel was given based on JC constitutive equation. After two times of modification，the error accuracy was improved nearly by 40%, the maximum error was less than 8%, and the applicable range of strain rate was expanded. According to the modified JC constitutive equation, the flow stress of B250P1 low alloy steel under different strain rates could be predicted well, and it could better satisfy the needs of engineering applications.