激光熔凝对高速火焰喷涂硬质合金层耐磨性的影响  

Influence of laser melting on wear resistance of high velocity flame sprayed cemented carbide coating

作　　者：龚仁政 樊湘芳[1] 胡巍[1] 王媛妮[1] 刘怀民[1] 

机构地区：[1]南华大学机械工程学院,湖南衡阳421001

出　　处：《金属热处理》2015年第4期81-84,共4页Heat Treatment of Metals

基　　金：湖南省自然科学衡阳联合基金(11JJ9012);湖南省高校科技创新团队支持计划(湘教通[2012]318号);湖南省重点学科建设项目(湘教发[2011]76号)

摘　　要：利用高速火焰喷涂在45钢表面制备了Ni60AA和DZ-WC-12Co硬质合金层,再采用5 k W连续CO2激光器进行激光熔凝。通过GX51金相显微镜观察显微组织,HXS-1000TAY维氏硬度计测量硬度分布,MM-W1B立式万能磨损试验机进行磨损试验。结果表明,激光熔凝显著地消除了硬质合金层中未熔硬质合金颗粒、孔洞及裂纹等缺陷,组织更加细小、均匀;激光熔凝后,硬质合金层的硬度提高,平均显微硬度高达647 HV0.3。在试验条件下,激光熔凝后的硬质合金层的摩擦因数从原来的0.1373降至0.0948,激光熔凝可明显改善涂层的耐磨性能。Ni60AA and DZ-WC-12Co cemented carbide coatings were prepared on 45 steel by high velocity flame spraying, then laser melted by 5 kW continuous wave CO2 laser. The microstructure was observed by Olympus GX51 microscope, the micro-hardness distribution was tested by HXY-1000TAY Vickers hardness tester and the wear test was carried out by MM-W1B vertical universal wear testing machine. The results show that laser melting can significantly eliminate the unmelted carbide particles, holes and cracks in coatings,and the microstructure is fine and uniform. After laser melting, the average micro-hardness of the carbide coatings is up to 647 HV0. 3. Under the experimental conditions, the friction coefficient of the coating after laser melting decreases from 0. 1373 to 0. 0948. The wear resistance of cemented carbide coatings can be significantly improved after laser melting.

关 键 词：涂层 硬质合金 激光熔凝 高速火焰喷涂 耐磨性 

分 类 号：TG156.99[金属学及工艺—热处理] TG115.58[金属学及工艺—金属学]