Al2O3-CoCrAlY 复合陶瓷激光熔覆层的组织与性能

研究了Ａｌ２Ｏ３－ＣｏＣｒＡｌＹ复合陶瓷涂层的组织结构、成分分布及其耐磨性能。结果表明：等离子喷涂层的组织呈层片状，面层由α－Ａｌ２Ｏ３和少量的γ－Ａｌ２Ｏ３组成，层间为机械结合界面，涂层平均硬度为８９７ＨＶ０．２。经激光重熔后的组织为单一的α－Ａｌ２Ｏ３柱状晶，在ＣｏＣｒＡｌＹ与基体间有界面相形成，其界面为冶金结合，层间存在着平缓的成分过渡；Ａｌ２Ｏ３与ＣｏＣｒＡｌＹ间的界面结合状况得到了明显的

STRUCTURE AND PROPERTIES OF LASER CLADDED Al2O3-CoCrAlY COMPOSITE CERAMIC COATINGS ON W18Cr4V STEEL

The wear resistance, structure and composition distribution of Al2O3/CoCrAlY composite ceramic coatings on W18Cr4V steel were studied. The results show that structure of plasma sprayed coatings is laminars in shape, and the Al2O3 top coating consists of -Al2O3 and a small amount of -Al2O3. There is a mechanically combined interface between Al2O3 and CoCrAlY coatings, and also between CoCrAlY and substrate. The average hardness of plasma sprayed Al2O3 coatings is about 897 HV0.2. The structure of coatings cladded by laser is columnar, which consists of -Al2O3. There is an interface phase of metallurgical combination and a little composition gradient was observed between CoCrAlY and substrate. The bonding of interface between Al2O3 and CoCrAlY has been improved obviously. The hardness of Al2O3 coatings cladded by laser is about 2 4792 691 HV0.2 and the wear resistance is 23 times that of plasma sprayed coatings. The wear mechanism is fatigue wear and abrasive wear.