摘要
The SiCp(20 %)reinforced cobalt-based alloy composite coatings deposited by laser cladding on IF steel were introduced.The microstructure across the whole section of such coatings was examined using optical microscope,scanning electron microscope(SEM)and X-ray diffractometer(XRD),and the wear resistance of the coatings was measured by MM-200 type wear testing machine.The results show that the SiCpis completely dissolved during laser cladding and the primary phase in the coatings isγ-Co.The other phases,such as Si2 W,CoWSi,Cr3 Si and CoSi2,are formed by carbon,silicon reacting with other elements existing in the melting pool.There are various crystallization morphologies in different zones,such as planar crystallization at the interface,followed by cellular and dendrite crystallization from interface to the surface.The direction of solidification changes from one direction perpendicular to interface to multi-directions at the central and upper regions of the clad.The wear resistance of the clad is improved by adding SiCp.
The SiCp(20 %)reinforced cobalt-based alloy composite coatings deposited by laser cladding on IF steel were introduced.The microstructure across the whole section of such coatings was examined using optical microscope,scanning electron microscope(SEM)and X-ray diffractometer(XRD),and the wear resistance of the coatings was measured by MM-200 type wear testing machine.The results show that the SiCpis completely dissolved during laser cladding and the primary phase in the coatings isγ-Co.The other phases,such as Si2 W,CoWSi,Cr3 Si and CoSi2,are formed by carbon,silicon reacting with other elements existing in the melting pool.There are various crystallization morphologies in different zones,such as planar crystallization at the interface,followed by cellular and dendrite crystallization from interface to the surface.The direction of solidification changes from one direction perpendicular to interface to multi-directions at the central and upper regions of the clad.The wear resistance of the clad is improved by adding SiCp.
基金
Item Sponsored by International Government Cooperation Projects of Sino-Korea(2002009)and Sino-America(01088013)
