摘要
The composite coatings were formed by plasma cladding Fe-based alloy（Fe-Cr-B-Si） added 10% , 30% and 50% （mass fraction） nickel-clad WC respectively on Q235 steel. The microstructure evolution and microhardness of the coatings were investigated. The WC particles were completely melted into the composites coating when 10% WC was added, however, when 30% or 50% WC was added, only part of them could be melted in the coatings. Two significantly different solidification microstructures were found. When WC content is 10% or 30%, the microstructure is mainly dendrites and inter- dendrite eutectics, while when the content of WC reaches 50% , it becomes remained WC particles, Fe3 W3 C carbide faceted dendrite and eutectics hypereutectic structure. The microhardness of these three coatings reaches 560- 600, 650 -810 and 920 - 1 100 HVo2 respectively, and is improved with the increasing of WC content.
The composite coatings were formed by plasma cladding Fe-based alloy（Fe-Cr-B-Si） added 10% , 30% and 50% （mass fraction） nickel-clad WC respectively on Q235 steel. The microstructure evolution and microhardness of the coatings were investigated. The WC particles were completely melted into the composites coating when 10% WC was added, however, when 30% or 50% WC was added, only part of them could be melted in the coatings. Two significantly different solidification microstructures were found. When WC content is 10% or 30%, the microstructure is mainly dendrites and inter- dendrite eutectics, while when the content of WC reaches 50% , it becomes remained WC particles, Fe3 W3 C carbide faceted dendrite and eutectics hypereutectic structure. The microhardness of these three coatings reaches 560- 600, 650 -810 and 920 - 1 100 HVo2 respectively, and is improved with the increasing of WC content.
