退火对化学镀Ni-W-P合金晶化及耐蚀性的影响  

Effects of Annealing on Corrosion and Crystal of Ni-W-P Coatings by Chemical Deposition

作　　者：李莎[1] 郭荣新 卞建胜[1] 钟浩 刘宏[1] 

机构地区：[1]山东轻工业学院机械与汽车工程学院,济南250353 [2]淄博市新材料研究所,淄博255040 [3]山东工业技师学院,潍坊261053

出　　处：《表面技术》2011年第5期9-12,84,共5页Surface Technology

基　　金：山东省自然科学基金资助项目(Y2006F40)

摘　　要：在不同温度下对制备的Ni-W-P合金镀层进行退火处理,利用X射线衍射技术定量分析了镀层的晶化、晶粒尺寸和晶格应变,采用扫描电镜(SEM)和光学显微镜观察了镀层腐蚀前后的表面形貌,并通过在0.5mol/L H2SO4溶液中的浸泡腐蚀速率和阳极极化曲线对退火前后镀层的耐蚀性进行了分析。结果表明:Ni-W-P镀层在镀态为非晶态结构,晶化温度高于400℃,镀层中有Ni3P相析出,且Ni3P相的晶粒尺寸大于Ni相,温度超过500℃时,两相的晶粒尺寸特征与之相反,各镀层的晶粒尺寸都保持在纳米级范围;镀层的晶格应变随退火温度的升高而降低;在700℃退火时,镀层的耐蚀性最高。All of the Ni-W P coatings were annealed at different temperature, crystallization, grain size and lattice strain of electroless Ni-W-P coatings were examined by XRD quantitative analysis method. The corrosion behavior was investigated by immersion and potentiodynamic polarization tests. The surface topographies of coatings before and after corrosion were analysed by scanning electron microscope （SEM） and optical microscope. The corrosion of coating before and after annealing was analyzed by the immersion corrosion rate and anodic polarization curve in 0. 5 mol/L H2SO4 solution. The results show that Ni-W P coating is amorphous structure, while at 400℃ precipitation of Ni3P phase occurs and its grain size is larger than that of Ni phase. When annealed temperature is above 500℃ ,characteristic of sizes of both phases reverses, but the size of all coatings remain in the range of nanoseale; Lattice strain descends with increase of annealing temperature. Corrosion resistance reaches maxima at 700℃.

关 键 词：化学沉积 Ni—W—P合金 晶粒尺寸 晶格应变 阳极极化 腐蚀速率 

分 类 号：TQ153.2[化学工程—电化学工业]