Research On Laser Cladding Wear And Corrosion Resistance Layers On Working Surface Of Plunger Pump Piston

Based on the the use of the plunger piston pump of poor working conditions,the paper explores how to use the technology of laser cladding to improve wear resistance and corrosion resistance on working surface.At the beginning of this paper,applying the finite element simulation software,ANSYS to simulate the temperature field of laser cladding.Using the technology of laser cladding to manufacture Ni60+TiC composite coating with different proportion on the surface of 45 steel.Studying macro morphology,microstructure,microhardness,wear resistance and corrosion resistance of the cladding layer.Research shows,laser cladding is a process of rapid melting and solidification,and the temperature field of laser cladding is a regular quasi steady state temperature field.The optimum process parameters of laser cladding is determined.There are differences between the surface of Ni60+TiC composite coating with different proportion.The surface of single Ni60 laser cladding coating is flat and compact.But the surfaces of Ni60+TiC cladding coating have some granular protuberances,and the surface of Ni60+10%TiC cladding coating has a few small holes.Compared with the substrate,surface hardness is greatly increased.Surface hardness of Ni60+TiC composite coating is higher than that of single Ni60 coating,and with the increase of adding amount of TiC in the cladding layer,micro-hardness of cladding layer has a gradually increasing trend.Compared with the substrate,the friction coefficient of laser cladding coatings is greatly reduced.The friction coefficient of Ni60+TiC composite coating is lower than that of single Ni60 coating,and the friction coefficient of Ni60+20% TiC composite coatings is best.The wear rate of laser cladding coatings is lower than that of the substrate.The wear rate of Ni60+TiC composite coating is lower than that of single Ni60 coating,and the wear rate of Ni60+20% TiC composite coating is lowest.Wear mechanism of substrate is given priority to plough cutting,but wear mechanism of laser cladding coating combines plough cutting and fatigue spalling.Along with the increase in content of TiC,plough cutting effect is gradually reduced and fatigue spalling is gradually increased.Corrosion resistance of laser cladding coating is superior to substrate.Corrosion resistance of Ni60+20% TiC composite coating and Ni60+30% TiC composite coating is better than that of single Ni60 coating.In the laser cladding process,laser with high energy illuminates cladding powder and makes it completely fused.Strong convection within the molten pool and its internal rapid solidification make it get uniform distribution of small hard phase particles and even organizational structure.Uniform microstructure structure and high density of coating plays a significant role in increasing wear resistance and corrosion resistance.