Study on Effect of Local Induction Tempering on Slanting Tension Property of High Strength Steel Bolts

The threaded end of 30CrMnSiNi2A steel bolt pieces was respectively subjected to local tempering in lead bath and local tempering in induction heating, and the effects of two local tempering processes on the hardness distribution and tensile properties at different deflection angles of the sample after tempering were studied. The results show that more uniform hardness distribution can be obtained after induction local tempering treatment. Meanwhile, the induction local tempering process can significantly improve the notch sensitivity of the material, and enhance the crack growth resistance and deformation compatibility of the sample.