Effects of Strain Rate on Mechanical Properties and Fracture Mechanisms in a Dual Phase Steel

Sharma, S. M., Mishra, K., Rodriguez, O., Whittington, W. R., Allison, P. G., Shrikant, S. P., Gokhale, A. M., Arun, M., & Thadhani, N. N. (2017). Effects of Strain Rate on Mechanical Properties and Fracture Mechanisms in a Dual Phase Steel. Dynamic Behavior of Materials. Conference Proceedings of the Society for Experimental Mechanics: Springer. 1, 209-216.

Strain rate sensitivity of sheet steels affects their formability and crashworthiness. This contribution reports strain rate sensitivity and effects of strain rate on fracture micro-mechanisms in a commercial dual phase sheet steel (DP590). Uniaxial tensile tests were performed at strain rates of 10−4/s, 1/s and 3200/s to characterize effects of strain rate on ultimate tensile strength and ductility. Fracture surfaces of the tested specimens were quantitatively characterized using stereological techniques to understand the fracture micro-mechanisms. Obtained data indicates that the basic fracture micro-mechanism remains the same with respect to strain rate but strain partitioning in ferrite and martensite is a strong function of strain rate.