WC粒度对WC-Ni钎涂耐磨涂层组织性能的影响

Effect of WC particle size on microstructure and properties of WC-Ni wear resistant brazing coating

钎涂粉末粒度是影响耐磨涂层性能的关键因素。研究WC粒度对WC-Ni钎涂耐磨涂层组织和性能的影响,采用镍芯药皮焊条,用火焰钎涂工艺制备3种不同WC粒度的WC-Ni耐磨涂层,并用扫描电镜、能谱仪、显微硬度计和洛氏硬度计对涂层的组织和性能进行分析。结果表明:随着WC粒度的增加,Ni钎料与WC增强相的冶金反应程度减弱;WC粒度为18~23μm时,涂层界面过度层中出现了长条状的Ni W相;WC粒度为250~380μm时,涂层的洛氏硬度最高,涂层的耐磨性最好。

Powder particle size is the key factor that affects wear resistance coating. The effect of WC granularity on the microstrueture and properties of WC-Ni brazing coatings was studied. Three WC-Ni wear-resistant coatings with different WC sizes were prepared by flame brazing technology. The microstrueture and properties of the coating were analyzed by scanning electron microscope,energy spectrometer,microhardness tester and rockwell hardness tester. The resuhs show that：With the increase of WC particle size,the metallurgical reaction degree of Ni solder and WC enhanced phase decreased. When WC particle size is 18-23 μm,long strip NiW phase appears in the overlayer of coating interface. When the WC particle size is 250-380μm,the rockwell hardness of the coating is the highest,and the coating has the best wear resistance.