摘要
为了研究纳米CeO2颗粒对激光熔覆层的组织和性能的影响,在Q235钢基体上制备了加入不同量纳米CeO2的N i基合金熔覆层,利用OLMPUS PME-3型光学显微镜,XD-3A型X射线衍射仪,HV-1000型显微硬度计,MM-200型环-块磨损试验机和扫描电镜等对激光熔覆层显微组织、相结构、显微硬度、磨损性能和磨损机理进行了研究。结果表明,在激光熔覆层中添加纳米CeO2能够细化组织,改变凝固组织的形态。当加入质量分数为1.5%的纳米CeO2时,熔覆层凝固组织形态为等轴树枝晶;生成了含Ce的新相Ce2N i21B6,明显提高了熔覆层的显微硬度和耐磨性;熔覆层磨损由严重磨损转化为轻微磨损。但是加入过量的纳米CeO2,硬度反而降低。
The microstructure and properties of laser clad coating are introduced after adding nano particles. Nickel-based alloy powder with different addition of nano-CeO2 is laser cladded onto Q235 steel substrate. The coating is examined to reveal the microstructure, phase composition, microhardness and wear resistance using optical microscope （OP）, X-ray diffractometer （XRD）, mierohardness tester, block-on-ring wear tester and scanning electron microscope （SEM） respectively. The results show that fine dendrite and equiaxed dendrite are observed by adding nuno-CeO2. Equiaxed dendrite across the section is obtained when the additive reaches to 1.5% （mass fraction）. A new phase（Ce2Ni21B6） is found. The microhardness and wear resistance of the coating are much higher than those of the substrate, and further improved by adding nuno-CeO2. But the hardness decreased when the additive amount is much high. The mechanism of these effects is also discussed.
出处
《激光技术》
CAS
CSCD
北大核心
2006年第3期228-231,共4页
Laser Technology
基金
安徽省教育厅自然科学重点科研资助项目(2005KJ038ZD)
安徽省科技厅资助项目(04022004)
