摘要
The integrated processing of chromizing and austempering(termed chro-austempering)treatments was proposed.The microstructure and properties of a medium-carbon high-strength bainitic steel treated by chro-austempering treatments were investigated by metallography,scanning vibrating electrode technique,electrochemical workstation,and microhardness test.The results show that the high-strength bainitic steel with carbide-free bainite as matrix and the chromized layers on surfaces was successfully fabricated by chro-austempering treatment.The hardness of surface layers was about 3.5 times that of the bainite matrix.Meanwhile,the corrosion started from exposed bainitic matrix and proceeded along the depth direction,testifying that the surface corrosion resistance was significantly improved by chro-austempering treatment due to the formation of Cr_(7)C_(3)and(Cr,Fe)7_(7)C_(3)on the surface.
基金
The National Natural Science Foundation of China(NSFC)(51874216 and 52104381)
the Key Project of Hebei Iron and Steel Group(HG219313)
the Open Fund of Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking(KF-20-4)
Natural Science Foundation of Hubei(2021CFB127)
China Postdoctoral Science Foundation(2021M702539).
