激光熔化沉积γ/NiMo近共晶合金的组织与耐磨性  

Microstructure and Wear Resistance of a Laser Melting-Deposited γ/NiMo Near-Eutectic Alloy

作　　者：陆晓锋[1] 王华明[1] 

机构地区：[1]北京航空航天大学材料学院激光材料成形制造实验室,北京100083

出　　处：《中国激光》2007年第4期559-563,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(50331010)重点资助项目

摘　　要：以Ni-Mo合金粉末为原料,利用激光熔化沉积技术制备出主要由高硬度NiMo金属间化合物和高强韧性镍基固溶体γ组成的γ/NiMo近共晶合金,分析了合金的显微组织并在室温干滑动磨损条件下测试了合金的耐磨性。结果表明,γ/NiMo近共晶合金组织细小、均匀致密;由于NiMo金属间化合物的高硬度与γ的高强韧性配合,合金在两种滑动速度时的磨损量均较低且几乎不随法向载荷的增加而变化,表现出优异的磨损载荷特性,而摩擦系数随法向载荷的增加显著降低,特别是在较高滑动速度时合金反而具有较低的磨损量和摩擦系数。合金在滑动速度0.93 m/s,法向载荷196 N时的磨损量仅为相同条件下淬火45#钢磨损量的1/10。A γ/NiMo near-eutectic alloy mainly consisting of NiMo intermetallic compound and Ni-based solid solution γ was fabricated by laser melting deposition process using Ni-Mo elemental powder blends. Microstructure and room temperature dry sliding wear resistance of the alloy at different sliding speeds and test loads were studied. The alloy has a homogeneous microstructure and better wear resistance even at higher sliding speed and test load. Wear volume loss of the alloy is extremely insensitive to increasing wear test load at each sliding speed while coefficient of friction drastically decreases with the increase of both sliding speed and test load, what＇s more, higher sliding speed brings lower wear volume loss and lower coefficient of friction, which is dominantly due to the combination of high hardness of the NiMo intermetallic compound and good toughness of the Ni-based solid solution γ. Wear volume loss of the alloy is only ten percent of that of hardened 0. 45% C steel under the same testing condition of 0.93 m/s sliding speed and 196 N test load.

关 键 词：激光技术 近共晶合金 耐磨性 NIMO 激光熔化沉积 

分 类 号：TG146[一般工业技术—材料科学与工程] TH117[金属学及工艺—金属材料]