喷涂距离对内孔HVOF喷涂纳米WC-10Co4Cr涂层组织及抗泥沙冲蚀性能的影响  

Influence of Spraying Distance on the Microstructure and Slurry Erosion Resistance of Nano WC-10Co4Cr Coating Prepared by Internal HVOF

作　　者：张磊 张凯 霍嘉翔 ROSHAN Pandey 陈小明 ZHANG Lei;ZHANG Kai;HUO Jia-xiang;ROSHAN Pandey;CHEN Xiao-ming(Key laboratory of Research on Hydraulic and Hydro-Power Equipment Surface Engineering Technology of Zhejiang Province,Standard&Quality Control Research Institute of Ministry of Water Resources,Hangzhou 310024,China;Water Machinery and Remanufacturing Technology Engineering Laboratory of Zhejiang Province,Hangzhou Machine Design&Research Institute of Ministry of Water Resources,Hangzhou 310024,China;Nepal Academy of Science and Technology,Kathmandu 999098,Nepal)

机构地区：[1]水利部产品质量标准研究所、浙江省水利水电装备表面工程技术研究重点实验室,浙江杭州310024 [2]水利部杭州机械设计研究所、水利机械及其再制造技术浙江省工程实验室,浙江杭州310024 [3]尼泊尔国家科学技术研究院,尼泊尔加德满都999098

出　　处：《稀有金属与硬质合金》2023年第5期36-43,共8页Rare Metals and Cemented Carbides

基　　金：浙江省“一带一路”国际科技合作项目(2019C04019);浙江省公益性技术应用研究计划项目(GC22E017317)。

摘　　要：利用内孔氧-丙烷超音速火焰喷涂技术在ZG0Cr13Ni5Mo不锈钢基材表面制备纳米WC-10Co4Cr涂层,分别通过45°和90°两种内孔喷枪研究了喷涂距离对涂层宏/微观组织及抗泥沙冲蚀性能的影响。采用X射线衍射仪(XRD)测试分析了涂层的物相成分,利用扫描电子显微镜(SEM)观察了涂层截面的微观形貌,并结合金相显微镜分析了孔隙率;通过维氏硬度计测试了涂层的显微硬度,利用粗糙度仪和光学轮廓仪表征了涂层表面的粗糙度及三维形貌;采用泥沙冲蚀磨损试验机对比研究了涂层与不锈钢基材的抗泥沙冲蚀性能,并结合SEM分析了冲蚀磨损机理。研究发现,45°和90°两种内孔喷枪所制备纳米WC-10Co4Cr涂层主要物相成分均为WC、W_(2)C和非晶态CoCr合金相,未受到喷涂距离的影响。短喷涂距离会导致涂层孔隙缺陷的产生,孔隙率随着喷涂距离的增大先下降后上升。喷涂距离对90°喷枪所制备涂层显微硬度的影响较小,而45°喷枪在喷涂距离增大到150 mm以后涂层硬度有下降趋势,两者最高硬度分别为1343.1 HV0.2和1275.4 HV0.2;对于两种喷枪,短喷涂距离会导致涂层表面产生凸起团聚颗粒,粗糙度随着喷涂距离的增大而降低。涂层抗泥沙冲蚀性能随喷涂距离的增大先升高而后逐渐下降,45°和90°内孔喷枪喷距分别为200 mm和250 mm时所制备涂层的抗泥沙冲蚀性能达到最高,分别是基材的7.03倍和8.05倍。WC-10Co4Cr涂层的泥沙冲蚀磨损机制主要是交变应力下的疲劳剥落,基材则为均匀的泥沙微切削。Nano WC-10Co4Cr coatings were prepared on ZG0Cr13Ni5Mo stainless steel by internal oxygen-propane HVOF spraying,and the effects of spraying distance on the macro/micro structure and slurry erosion resistance of the coatings were investigated by two types of internal guns at 45°and 90°.The phase composition of the coatings was measured by X-ray diffraction(XRD),the microstructure of cross section of the coatings was observed by scanning electron microscope(SEM),and the porosity was analyzed by metallographic microscope.The microhardness of the coatings was measured by Vickers hardness tester while the surface roughness and 3D morphology were characterized using roughness meter and optical profilometer.The slurry erosion resistance of the coatings and stainless steel substrate was compared using slurry erosion tester,and the erosion wear mechanism was analyzed by SEM.The results show that the main phase composition of the coatings prepared by 45°and 90°internal guns consists of WC,W_(2)C and amorphous CoCr alloy phases,which are not affected by the spraying distance.Short spraying distances result in the formation of pores defects in the coatings and the porosity initially decreases and then increases with the increase of spraying distance.Though the microhardness of the coating prepared by the 90°spray gun receives minimal influence from the spraying distance,the coating microhardness of the 45°spray gun shows a decreasing trend after the spraying distance increases to 150 mm,and the maximum hardness va-lues of the coatings prepared by the two spray guns are 1343.1 HV_(0.2)and 1275.4 HV_(0.2),respectively.For both guns,short spraying distances lead to the formation of raised agglomeration particles on the coating surface,while the roughness decreases with the increasing spraying distance.With the increase of the spraying distance,the erosion resistance of the coatings increases at first and then decreases gradually,and the highest erosion resistance of the coatings prepared by 45°and 90°internal guns is ac

关 键 词：内孔HVOF 喷涂距离 喷涂角度 纳米WC-10Co4Cr涂层 抗泥沙冲蚀性能 冲蚀机理 

分 类 号：TG174.4[金属学及工艺—金属表面处理]