摘要
The coarse WC particles ceramic-metal com- posite coatings with WC density of 67 wt-% and thickness of 1.0-1.2 mm have been cladded on 20Ni4Mo steel surface by a 2 kW CO_2 laser.The sintered WC particles with the size of 600-1000 μm are chosen as the main strengthening phase, Ni-base self-flux alloy as the binder in the compo- site coatings.The microstructure and microhardness of both WC particles and binder are analysed.The rigid ball indention with acoustic emission technique is used to evaluate the brittleness of the coating.Finally,the abrasive wear resistance of the coating is tested.Besides,the coatings with the same ratio and size of WC parti- cles in low carbon steel tube rod were cladded on 20Ni4Mo steel by atomic hydrogen welding tech- nique and analysed by the same way,their results are compared.
The coarse WC particles ceramic-metal com- posite coatings with WC density of 67 wt-% and thickness of 1.0-1.2 mm have been cladded on 20Ni4Mo steel surface by a 2 kW CO_2 laser.The sintered WC particles with the size of 600-1000 μm are chosen as the main strengthening phase, Ni-base self-flux alloy as the binder in the compo- site coatings.The microstructure and microhardness of both WC particles and binder are analysed.The rigid ball indention with acoustic emission technique is used to evaluate the brittleness of the coating.Finally,the abrasive wear resistance of the coating is tested.Besides,the coatings with the same ratio and size of WC parti- cles in low carbon steel tube rod were cladded on 20Ni4Mo steel by atomic hydrogen welding tech- nique and analysed by the same way,their results are compared.
