Influence of Annealing Temperature on Microstructure and Properties of the Hot-Stamping Boron Steel

The effect of different annealing temperature on microstructure and properties of the hot-stamping boron steel were studied.The results show that the yield strength of the test steel is reduced with increasing annealing temperature, only at 790°C,the specimen yield strength increased slightly, and showed a significant downward trend after 790°C.The specimen tensile strength and hardness with the change of the same trend when annealing temperature changes.And through the test we can see,at 760°C ,the test steel has entered a two-phase region,the test steel gain ferrite and pearlite when it is annealed below the temperature,it is easy to appear martensite microstructure when it is annealed in the higher temperature,and lead to the strength and hardness of the rise.