机械工程材料，
MATERIALS FOR MECHANCAL ENGINEERING DOI;10,11973/jxgccl201508021
2015年8月第39卷第8期Vol.39No,8Aug,2015
微米和纳米Cr3Cz对Co40合金等离子堆焊层组织
与性能的影响斯松华，于婉萍，张磊，李飞
（安徽工业大学材料科学与工程学院，马鞍山243002）
摘要：采用等离子堆焊技术在低破钢表面分别制备了Co40合金堆焊层以及分别添加30%（质量分数)微米和纳米Cr;C的Co40合金(Cr,Ce/Co)复合堆焊层，对比研究了添加微米和纳米Cr;C 对Co40合金堆焊层组织与磨损性能的影响。结果表明：Co40合金堆焊层的组织主要为发达柱状晶及其间的网状共晶；微米Cr;Cz/Co复合堆焊层中的柱状晶明显被打断、碎化，生长方向性减弱，且其组织更加均匀和细小；纳米Cr,C/Co复合堆焊层的结晶方式则由亚共晶转变为共晶，其组织主要由共晶组织组成，且进一步细化和均匀化；与Co40合全堆焊层相比，微米Cr,C/Co复合堆焊层的硬度和耐磨性
分别提高了37%和29%，而纳米Cr;C/Co复合堆焊层的硬度和耐磨性则分别提高了50%和55%。关键调：等离子堆焊;Co40合金；纳米CrCz；组织；耐磨性
文章编号：1000-3738(2015)08-0094-04
中图分类号：TG456.2
文献标志码：A
EffectsofMicronandNanoCr:ConMicrostructureandProperties
ofCo40AlloyPlasmaSurfacingLayer SI Song-hua, YU Wan-ping, ZHANG Lei, LI Fei
(School of Material Science and Engineering, Anhui University of Technology, Maanshan 243002, China) Abstract; The Co40 alloy surfacing layer, Cr,C,/Co composite surfacing layers with 30wt.% micron and
nano Cn,C respectively on the surface of low-carbon steel were obtained by plasma surfacing. Effects of micron Cr,C and nano-Cr,C on the microstructure and properties of the Co4o alloy surfacing layer were studied comparatively. Results show that the Co40 alloy surfacing layer was composed of developed columnar crystals and reticular eutectic structure between the dendrites. The dendrites of micron-Cr, C/Co composite surfacing layer were aae microstructure was refined and homogenized. The crystallization way of nano-Cr,Ce/Co composite surfacing layer eee structure, which was further refined and became more homogeneous, Compered with the Co40 alloy surfacing layer, the hardness and wear resistance of the micron-Cr C,/Co composite surfacing layer were increased by 37% and 29%, while the hardness and wear resistance of the nano-Cr; Ce /Co surfacing layer were increased by 50% and 55%.
Key words: plasma surfacing; Co4o alloy; nano-Cr,C2; microstructure; wear resistance
0引言
机械工程零部件失效的主要原因之一是表面的磨损，由此造成的经济损失较大{"]。等离子堆焊技术是一种有效的表面强化方法，通过在零件表面堆
收稿日期：2014-06-13修订日期：2015-05-30
作者简介：斯松华（1966一），男，安徽太湖人，教授，硕士， 94
万方数据
焊一层具有特殊性能的合金，可以提高基体材料的表面性能，从而延长零件的使用寿命[2]。等离子堆焊钻基合金层常被用于高温工作环境中，通过添加陶瓷颗粒来提高其磨损性能[3-4]。Cr;Cz具有高熔点、高硬度等特点，其作为陶瓷增强相应用于表面涂层的研究已有很多报道[3-}，但之前研究人员所使用的Cr;C陶瓷颗粒多为微米级，它与基体的相容性有待进一步改善。