激光功率对激光熔覆NiCoCrAlY涂层组织及性能的影响  

Effects of Laser Power on Microstructure and Properties of Laser Cladding NiCoCrAlY Coating

作　　者：刘思远 李玉新[1] 杨宜鑫 陈博文 LIU Si-yuan;LI Yu-xin;YANG Yi-xin;CHEN Bo-wen(School of Materials Science and Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学材料科学与工程学院,太原030051

出　　处：《精密成形工程》2022年第3期50-57,共8页Journal of Netshape Forming Engineering

基　　金：国家自然科学基金山西煤基低碳联合基金(U1810112)。

摘　　要：目的为了提高17-4PH的耐腐蚀性能和摩擦磨损性能,采用激光熔覆技术在17-4PH不锈钢表面制备NiCoCrAlY涂层。方法利用X射线衍射(XRD)、扫描电镜(SEM)、显微维氏硬度计、电化学工作站和往复摩擦磨损试验机等研究不同激光功率下NiCoCrAlY涂层的相组成、微观形貌、硬度、耐腐蚀性能和摩擦磨损性能。结果NiCoCrAlY涂层中包含γ/γ'相和β相,随着激光功率的增大,未完全熔融的NiCoCrAlY粉末颗粒、夹渣和孔隙等缺陷逐渐减少,直至消失。当激光功率为2000 W时,NiCoCrAlY涂层的组织均匀致密,无夹渣和气孔等缺陷。NiCoCrAlY涂层的硬度、耐腐蚀性能及摩擦磨损性能均高于基体。当激光功率为2000 W时,NiCoCrAlY涂层硬度(490HV_(0.1))最高,摩擦磨损性能(摩擦因数为0.57)和耐腐蚀性能最优。结论最优的激光功率为2000 W,此工艺参数下制备的NiCoCrAlY涂层有效提高了17-4PH不锈钢的硬度、耐腐蚀性能及摩擦磨损性能。The work aims to prepare NiCoCrAlY coating on the surface of 17-4PH stainless steel by laser cladding technol-ogy,so as to improve the corrosion resistance and friction and wear properties of 17-4PH.Phase composition,microstructure,hardness,corrosion resistance and friction and wear properties of the NiCoCrAlY coating prepared with different laser powers were studied by means of X-ray diffraction(XRD),scanning electron microscopy(SEM),Vickers hardness tester,electro-chemical workstation and reciprocating friction and wear tester.The microstructure of the NiCoCrAlY coating consisted ofγ/γ'phase andβphase.With the increase of the laser power,the defects such as incomplete molten NiCoCrAlY powder particles,slag inclusions and pores gradually decreased and finally disappeared.When the laser power was 2000 W,the microstructure of the NiCoCrAlY coating was uniform and dense,without defects such as slag inclusion and porosity.The hardness,corrosion re-sistance and friction and wear properties of NiCoCrAlY coating were higher than those of the substrate.When the laser power was 2000 W,NiCoCrAlY coating had the highest hardness(490HV_(0.1)),friction and wear properties(friction coefficient 0.57)and corrosion resistance were the best.The optimal laser power is 2000 W.The NiCoCrAlY coating prepared under this process parameter effectively improves the hardness,corrosion resistance and friction and wear properties of 17-4PH stainless steel.

关 键 词：激光熔覆 NICOCRALY涂层 硬度 耐腐蚀性能 摩擦磨损性能 

分 类 号：TG174.44[金属学及工艺—金属表面处理]