Microstructure and Properties of Fe-based Alloy Coating by Laser Cladding
Author of the article:QIAN Shaoxiang
Author's Workplace：School of Modem Equipment Manufacturing,Zhenjiang College,Zhenjiang 21202,China
Key Words：laser cladding Fe-based coating microstructure micro-hardness corrosion resistance
Abstract：
The Fe-based coating was prepared on the surface of DH36 steel by laser cladding.XRD,SEM and micro-hardness tester were used to analyze the phase composition,microstructure and micro-hardness of the coating.The corrosion resistance of Fe-based coatings and substrates was analyzed in artificial seawater by polarization curves.The result show that the coating is fairly bonded to the substrate,(Cr,Fe)7C3,Fe3C hard phase and double dense oxide films are existed in the coating.The microstructure of the bonding zone of the coating is mainly composed of plane crystal and columnar crystal growing upward directionally while that of the upper and middle parts is consists of fine dendrites,due to the combined effect of solid solution strengthening,carbide dispersion strengthening and fine grain strengthening of alloy elements,the average micro-hardness of the coating is 1 026.11 HV0.2,which is about 5.21 times higher than that of the matrix,the corrosion resistance of the coating has been significantly improved.
