Experimental Study on Residual Stresses of Al2O3 Coating by Laser Re-Melting
The surface of Al2O3 coating sprayed on 40Cr substrate was re-melted with high power continuous CO2 laser, and its micro-hardness and residual stresses were measured, respectively. The strengthening mechanism of Al2O3 coating by laser re-melting was analyzed and discussed. The experimental results shown that the surface of Al2O3 coating by laser re-melting is neat and smooth, and its compositions are even, its structures are compact, and Al2O3 coating is evenly distributed in its surface with grain forms, and its micro-hardness increases about 200%; Residual stress of Al2O3 coating by laser re-melting is changed into compressive stress from tensile stress, which is benefit to improving bonding strength of coating-substrate interface.
Yingxue Yao, Dunwen Zuo and Xipeng Xu
D. J. Kong et al., "Experimental Study on Residual Stresses of Al2O3 Coating by Laser Re-Melting", Key Engineering Materials, Vols. 431-432, pp. 446-449, 2010