Serrated Flow in an 11Cr Ferritic/Martensitic Steel

Serrated flow behavior of an 11Cr ferritic/martensitic steel was investigated through tensile tests at initial strain rates of 2×10-510-3 s-1 at temperatures ranging from room temperature to 973 K. Serrated flow occurred at three temperature regions of room temperature, 573 K and 773973 K when tensile tests were conducted at a strain rate of 2×10-4 s-1. Serrations are also observed in the steel during tension at temperatures of 573 K and 773973 K at a strain rate of 2×10-5 s-1. With increasing tensile temperature, the yield stress and ultimate tensile stress of the steel were gradually decreased and quickly dropped at temperatures higher than 773 K, while the elongation of the steel was decreased to a minimum at 600 K, and then dramatically increased at temperatures higher than 600 K.