Y_2O_3对W-4.9Ni-2.1Fe合金摩擦磨损行为的影响

采用高能球磨和放电等离子体烧结技术联合制备W-4.9Ni-2.1Fe-xY_2O_3高密度合金,利用洛氏硬度计、X射线衍射仪、往复式摩擦磨损试验机、三维轮廓仪等对合金的显微组织、力学性能和摩擦磨损行为进行研究。结果表明:适量稀土氧化物Y_2O_3掺杂,可以有效抑制烧结过程中晶粒的长大,使黏结相和钨颗粒均匀分布,提高合金的相对密度、硬度及摩擦磨损性能。当过量添加Y_2O_3时,Y_2O_3易于在晶界处偏聚,抑制晶粒长大效果减弱,合金的力学性能和摩擦性能均出现不同程度的下降;因此,Y_2O_3添加应适量,而当其添加量为0.4%(质量分数)时,合金综合性能最优。

Effect of Y2O3 on Friction and Wear Behavior of W-4.9Ni-2.1Fe Alloy

The W-4.9Ni-2.1Fe alloy with different addition of Y2O3was prepared by high energy ball milling and spark plasma sintering techniques,the microstructure,mechanical property,friction and wear behavior of the high density alloy were investigated by the Rockwell hardness tester,X-ray diffractometer,reciprocating friction and wear tester,3D profiler,etc.The results show that adequate doping of the trace Y2O3 can effectively inhibit the grain size,promote the γ-(Ni,Fe) bonding phase and tungsten particles uniformly distribute,increase the relative density,hardness,friction and wear properties.But the excessive Y2O3 addition can easily aggregate at grain boundary,weaken the inhibition effect,and decrease the mechanical and wear properties of the alloy.So the addition of Y2O3 should be appropriate.When the adding mass fraction of Y2O3 particles is 0.4％,the comprehensive performance of the alloy is the best.