Using different proportional mixtures of Ni-coated MoS_2, TiC and pure Nipowders, new typical wear resistant and self-lubricant coatings were formed on low carbon steel bylaser cladding process. The microstractures an...Using different proportional mixtures of Ni-coated MoS_2, TiC and pure Nipowders, new typical wear resistant and self-lubricant coatings were formed on low carbon steel bylaser cladding process. The microstractures and phase composition of the composite coatings werestudied by SEM and XRD. The typical microstructure of the composite coating is composed ofmulti-sulfide phases including binary element sulfide and ternary element sulfide, gamma-Ni, TiC andMo_2C. Wear tests were carried out using an FALEX-6 type pin-on-disc machine. The frictioncoefficient and mass loss of three kinds of MoS_2/TiC/Ni laser clad coatings are lower than those ofquenched 45 steel, and the worn surfaces of the laser cladding coatings are very smooth. Because ofhigh hardness combined with low friction, the laser cladding composite coating with a mixture of 70percent Ni-coated MoS_2, 20 percent TiC and 10 percent pure Ni powder presents better wearbehaviors than the composite coating with other powder blends. The composition analysis of the wornsurface of GCrlS bearing steel shows that the transferred film from the laser cladding coating tothe opposite surface of GCrl5 bearing steel contains an amount of sulfide, which can change themicro-friction mechanism and lead to a reduced friction coefficient.展开更多
文摘Using different proportional mixtures of Ni-coated MoS_2, TiC and pure Nipowders, new typical wear resistant and self-lubricant coatings were formed on low carbon steel bylaser cladding process. The microstractures and phase composition of the composite coatings werestudied by SEM and XRD. The typical microstructure of the composite coating is composed ofmulti-sulfide phases including binary element sulfide and ternary element sulfide, gamma-Ni, TiC andMo_2C. Wear tests were carried out using an FALEX-6 type pin-on-disc machine. The frictioncoefficient and mass loss of three kinds of MoS_2/TiC/Ni laser clad coatings are lower than those ofquenched 45 steel, and the worn surfaces of the laser cladding coatings are very smooth. Because ofhigh hardness combined with low friction, the laser cladding composite coating with a mixture of 70percent Ni-coated MoS_2, 20 percent TiC and 10 percent pure Ni powder presents better wearbehaviors than the composite coating with other powder blends. The composition analysis of the wornsurface of GCrlS bearing steel shows that the transferred film from the laser cladding coating tothe opposite surface of GCrl5 bearing steel contains an amount of sulfide, which can change themicro-friction mechanism and lead to a reduced friction coefficient.
