激光熔覆制备Fe90/WC复合涂层组织及性能研究

Study on Metallographic Structure and Performance of Fe90/WC Composite Coating Prepared by Laser Cladding

采用高速激光熔覆系统,以中心送粉的方式在45钢表面制备不同WC含量的Fe90/WC复合涂层,利用扫描电镜、数显维氏硬度计对涂层的微观结构和显微硬度进行了分析,并结合高速射流加沙冲磨仪对涂层的抗冲磨特性进行研究。结果表明:熔覆层与基体间有良好的冶金结合,界面处无气孔、裂纹等缺陷,组织性能良好。熔覆层微观硬度随WC添加量增加而提高,WC质量百分比为60%时,显微硬度为728 HV0.2,相当于纯Fe90涂层的2.4倍。合适的WC含量能明显提高涂层的抗冲磨性能,WC质量百分比为40%时,冲蚀失重要明显低于其它几组熔覆样品。

A series of Fe90 coating containing different concentration of WC were prepared by laser cladding,which is based on the internal laser coaxial-powder feeding technology.The inverted metallurgic microscope and vickers hardness tester were used to investigate the microstructure and microhardness of the composite coatings.The slurry jet erosion tester was also employed to study the erosion resistance.The results show that the coating is compact and has a good metallurgical bonding with the substrate.Crack,holes and other defects are also negligible.The microhardness of the coatings is increased with the addition of WC,it reaches 728 HV0.2 when WC concentration is 60%,which is equal to 2.4 times than that of Fe90 coating without WC.It is also revealed that a suitable amount of WC may lead to excellent anti-erosion performance,when it is 40%,the mass loss is obviously lesser than others.