热处理对Ni-P/纳米Al_2O_3复合镀层组织及耐腐蚀性能的影响  

INFLUENCE OF HEAT TREATMENT ON MICROSTRUCTURE AND CORROSION RESISTANCE OF Ni-P/NANO-Al_2O_3 COMPOSITE COATING

作　　者：彭成章[1] 朱玲玲[1] 

机构地区：[1]湖南科技大学湖南省机械设备健康维护重点实验室,湘潭411201

出　　处：《中国腐蚀与防护学报》2011年第3期179-183,共5页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然基金资助项目(50764004);湖南省科技计划项目(2010FJ3093);湖南省高校科技创新团队支持计划项目资助

摘　　要：采用脉冲电沉积方法在Q235钢表面制备Ni-P/纳米Al_2O_3复合镀层,对复合镀层进行200～400℃的热处理。利用X射线衍射仪分析复合镀层的组织结构,用电化学极化曲线和扫描电镜(SEM)研究复合镀层在3.5%NaCl和10%H_2SO_4溶液中的腐蚀行为。结果表明,纳米Al_2O_3颗粒推迟热处理过程中复合镀层内Ni_3P相的析出,其晶化温度高于Ni-P合金镀层;镀态及300℃热处理复合镀层在两种腐蚀介质中均表现出优异的耐腐蚀性能,400℃热处理复合镀层的耐腐蚀性能下降,镀层表面发生点蚀。The Ni-P/nano-A1203 composite coating on Q235 steel was prepared by pulse electroplating, the composite coatings were heat-treated at temperature of 200-400 ℃. The microstructure of the composite coatings was identified by X-ray diffraction, the corrosion behavior of the composite coatings in 3.5% NaC1 and 10% H2SO4 solutions was studied by the linear polarization measurements and scanning electron microscope （SEM）. The results show that nano-A1203 particles retard precipitating of Ni3P phase in composite coating, the crystallization temperature of the composite coating is higher than that of Ni-P alloy coating. The as-deposited and after 300℃ heat-treated composite coatings revealed better corrosion resistance in two corrosive solutions. The corrosion resistance of after 400℃ heat-treated composite coatings decreased. The corrosion behavior is pitting corrosion.

关 键 词：热处理 脉冲电沉积 Ni-P/纳米Al2O3复合镀层 耐腐蚀性 

分 类 号：TG176[金属学及工艺—金属表面处理]