A hard coating free of obvious defects is produced on a Ti–6Al–4V (TC4) alloy substrate by means of tungsten inert gas clad (TIGC) of the Deloro22–WC–La2O3 mixed powders, which greatly increased the surface performance of the substrate. Test results indicated that large quantities of needle-shape precipitates were formed in the Deloro22–WC TIGC coating, increasing the microhardness significantly, and also lots of pores are produced in this coating, weakening the wear resistance. It was noted that a fine/compact microstructure is obtained in the Deloro22–WC–La2O3 TIGC coating, also the defects cannot be observed obviously. La2O3 addition can effectively improve the fluidity of melt and hinder the growth of grains in TIGC pool, favoring a fine/compact microstructure to be produced, and also improving the wear property of the TIGC coating.

中文翻译：

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La2O3改性钨惰性气体包覆复合涂层的显微组织性能

借助 Deloro22-WC-La 的钨惰性气体包覆 (TIGC) 在 Ti-6Al-4V (TC4) 合金基体上生成无明显缺陷的硬涂层2○3混合粉末，大大提高了基材的表面性能。试验结果表明，Deloro22-WC TIGC涂层中形成了大量针状析出物，显着提高了显微硬度，同时涂层产生了大量气孔，削弱了耐磨性。值得注意的是，在 Deloro22-WC-La 中获得了精细/致密的微观结构2○3TIGC涂层，也没有明显观察到缺陷。拉2○3添加能有效改善熔体的流动性，阻碍TIGC熔池中晶粒的生长，有利于形成细密致密的显微组织，同时也提高了TIGC涂层的耐磨性能。