高速电弧喷涂FeMnCrNi/Cr_(3)C_(2)涂层的工艺优化及磨损性能

Process optimization and wear performance of high velocity arc spraying FeMnCrNi/Cr_(3)C_(2) coating

采用高速电弧喷涂技术在Q235钢表面制备了FeMnCrNi/Cr_(3)C_(2)涂层。通过正交试验研究了喷涂电压、喷涂电流和喷涂距离对涂层形貌及性能的影响,获得了涂层制备的最佳工艺参数。利用扫描电镜、X射线衍射仪、能谱仪、显微硬度仪与激光共聚焦显微镜等研究了最佳工艺参数下制备的FeMnCrNi/Cr_(3)C_(2)涂层的形貌及性能。结果表明:影响涂层性能的主次因素顺序为:喷涂距离、喷涂电压、喷涂电流。最佳工艺参数为:喷涂电压31 V、喷涂电流240 A、喷涂距离200 mm。采用最佳工艺参数制备的涂层孔隙率为1.99%,显微硬度为719 HV0.1,是Q235钢的3.5倍,涂层的平均磨痕宽度、深度和截面积分别为281.95μm、4.42μm和564.81μm2,相比Q235钢分别减小了60%、72%和89%,具有更优的耐磨性;涂层的主要磨损形式为磨粒磨损。

FeMnCrNi/Cr_(3)C_(2) coating was prepared on the surface of Q235 steel by high velocity arc spraying technology.The effects of spraying voltage,spraying current and spraying distance on morphology and properties of the coating were studied by orthogonal test,and the optimum process parameters of the coating preparation were obtained.The morphology and properties of the FeMnCrNi/Cr_(3)C_(2) coating prepared with the optimum process parameters were studied by means of scanning electron microscopy,X-ray diffractometer,energy spectrometer,microhardness tester and laser confocal microscopy.The results show that the order of the primary and secondary factors affecting coating performance is:spraying distance,spraying voltage,and spraying current.The optimum process parameters are:spraying voltage of 31 V,spraying current of 240 A and spraying distance of 200 mm.The porosity of the coating prepared with the optimum process parameters is 1.99%,the microhardness is 719 HV0.1,which is 3.5 times that of the Q235 steel,the average wear scar width,depth and cross section area of the coating are 281.95μm,4.42μm and 564.81μm2,respectively,which are 60%,72%and 89%lower than that of the Q235 steel,respectively,shows good wear resistance.The main wear mechanism of the coating is abrasive wear.