Research on Impact Strengthening and Thermal Stability of Normalizing 45 Steel

The bar-shaped normalizing 45 steel was subjected to impact strengthening at room temperature, the load was applied to the cross section of the specimen, and the microhardness of the specimen after impact strengthening was tested. The normalizing 45 steel before and after impact strengthening was aged and heated to 450 ℃ for 10-40 min. The microhardness of the specimens was tested. XRD test was carried out on the impact strengthened samples before and after aging treatment.The results show that the impact strengthening can improve the microhardness of normalized 45 steel, and the value is increased by 45HV. However, the hardness distribution on the cross section of the sample is not uniform, showing an upward trend from the center to the edge. Aging treatment can improve the microhardness of the specimen after impact strengthening,the internal structure of the alloy changeds from pearlite to tortenite, and the whole alloy shows good thermal stability. XRD test results show that the content of the main alloy elements in the sample changes locally, and then verify that the aging treatment can improve the microhardness of the impact strengthening sample from the point of view of the element content.This study is helpful to provide reference for the improvement of the application performance of 45 steel.