氧化铝涂层的超音速等离子喷涂参数影响及硬度分析  

Parameter Effect and Microhardness Analysis of Al_2O_3 Coatings Prepared by the Supersonic Plasma Spraying Technique

作　　者：毛杰[1] 宋进兵[1] 邓畅光[1] 黄科[1] 

机构地区：[1]广州有色金属研究院,广州510651

出　　处：《表面技术》2014年第4期110-114,141,共6页Surface Technology

基　　金：国际科技合作项目(2011DFB50030);广东省引进创新科研团队计划(2011C007)~~

摘　　要：目的初步明确超音速等离子喷涂参数对涂层的影响规律,优化工艺参数。方法采用超音速等离子喷涂技术制备Al2O3陶瓷涂层,对涂层进行表征,分析喷涂电流I、等离子发生气体压力Pair、喷距d对涂层显微结构的影响。基于涂层显微硬度HV设计工艺优化试验,建立喷涂参数与显微硬度之间的回归方程。结果 I=260 A或Pair=0.55 MPa时,涂层是α-Al2O3和γ-Al2O3双相复合结构;I=340 A或Pair=0.35 MPa时,涂层几乎全由γ-Al2O3相组成,基本不含有未熔颗粒;喷距变化对涂层相组成的影响不显著。I或d增大,或者Pair降低,显微硬度都呈增大趋势。结论在实验范围内,超音速等离子喷涂Al2O3涂层的显微硬度最优工艺是:Pair=0.35 MPa,I=340 A,d=230 mm。Objective To preliminarily clarify the effect of parameters on coatings in supersonic plasma spraying and to obtain the optimal process parameters. Methods Al2 O3 ceramic coatings were prepared by the supersonic plasma spraying technique. The microstructure and properties of Al2 O3 coating were characterized and the effect of spraying parameters such as spraying current, pressure of plasma gas and spray distance were also discussed. According to the response surface methodology, the optimization experiment with three factors and three levels was designed and the regression equation was established between the influencing factors and the response value, thickness. Results When I=260 A or Pair =0. 55 MPa, the coating was a dual-phase composite structure consisting of α-Al2 O3 and γ-Al2 O3 . When I=340 A or Pair = 0. 35 MPa, the coating was almost fully deposited into the γ-Al2 O3 phase, substantially containing no unmelted particles. Change in spraying distance had no significant effect on the phase composition of the coating. When I or d increased or Pair reduced, HV tended to increase. Conclusion In the experimental range, the optimal process parameters for microhardness of supersonic plasma spray were Pair =0. 35 MPa, I=340 A and d=230 mm.

关 键 词：超音速等离子喷涂 Al2 O3 涂层 喷涂参数 显微结构 工艺优化 显微硬度 

分 类 号：TG174.442[金属学及工艺—金属表面处理]