热处理对铝锂合金化学镀镍-磷层性能的影响  

Effects of Heat Treatment on Properties of Electroless Ni-P Coating on Al-Li Alloy

作　　者：董成通 刘刚[1] 高顺长 廖兴华 郭民城 DONG Cheng- tong;LIU Gang;GAO Shun- chang;LIAO Xing- hua;GUO Min- cheng(Department of Materials Science and Engineering, Nanchang Aviation University, Nanchang 330063, Chin)

机构地区：[1]南昌航空大学材料科学与工程学院,江西南昌330063

出　　处：《材料保护》2018年第5期98-102,共5页Materials Protection

摘　　要：为延长铝锂合金的使用寿命,提高其硬度、耐磨性和耐腐蚀性能,在2197铝锂合金表面作化学镀镍处理,并对其进行热处理来改善性能。利用扫描电子显微镜(SEM)、INCA型能谱仪(EDS)、中性盐雾试验(NSS)等分析了化学镀镍层的组成成分、组织结构、表面形貌、结合力和耐腐蚀性能。结果表明:在2197铝锂合金表面获得的化学镀镍层为含磷量14.11%的高磷镀镍层;不经热处理的化学镀镍层的结合力等级为2级,经热处理后其结合力等级为0级,当热处理温度过高(一般超过300℃)时,其结合力降为1级;化学镀镍层经120 h中性盐雾试验后,未热处理的化学镀镍层的耐腐蚀时间仅为48 h,耐腐蚀等级为5级,而热处理后其耐腐蚀时间延长至72 h,耐腐蚀等级为8级,热处理温度升至450℃后其耐腐蚀等级降为7级。适当的低温热处理能有效改善铝锂合金表面化学镀镍层与基体之间的结合力及提高化学镀镍层的耐腐蚀性能。In order to prolong the service life of Al- Li alloy and improve its hardness, wear resistance and corrosion resistance, electroless nickel plating on 2197 A1-Li alloy was carried out, and then the nickel coating was treated by heat-treatment to improve the performance. The composition, microstructure, surface morphology, coating adhesion and corrosion resistance of electroless nickel deposits were analyzed by scanning electron microscopy （SEM）, energy dispersive spectrometer （EDS） and neutral salt spray test （NSS）. Results showed that the elec- troless nickel coating on the surface of the 2197 A1-Li alloy was a phosphorus-rich nickel coating with a phosphorus content of 14.11%. Without heat-treatment, nickel coating adhesion grade was 2 whereas after heat-treatment the adhesion grade was 0. When the heat-treatment tempera- ture was too high （ more than 300 ℃ ）, the adhesion of nickel coating was reduced to grade 1. The neutral salt spray test （ 120 h） of electroless nickel coating showed that the corrosion resistance time of the nickel film without heat-treatment was only 48 h and the corrosion resistance grade was 5, while the corrosion resistance time of the nickel film after heat-treatment was prolonged to 72 h and the corrosion resistance grade was 8. When the nickel film was treated at 450 ℃, the corrosion resistance grade was decreased to 7. Proper low temperature heat-treatment effectively improved the adhesion between electroless nickel coating and substrate and improved the corrosion resistance of the electroless nickel coating on A1- Li alloy.

关 键 词：铝锂合金 化学镀镍 热处理 耐蚀性 结合力 表面形貌 

分 类 号：TG174.44[金属学及工艺—金属表面处理]