硫酸盐体系电沉积镍钨合金工艺研究

发布时间：2018-07-05 20:14

  本文选题：镍钨合金 + 电镀　； 参考：《表面技术》2017年07期

【摘要】：目的探究硫酸盐体系镀液中柠檬酸浓度、钨酸钠浓度及镀层热处理工艺,对镍钨合金镀层中钨含量、镀层硬度、镀层微观形貌和物相组成的影响。方法采用合金电沉积方法,以低碳钢为基体,在不同成分的镀液中制备了一定厚度的镍钨合金镀层,然后用不同的热处理工艺进行后处理。用扫描电镜(SEM)及其自带的EDS能谱观察镀层的微观形貌,检测镀层的钨含量。使用X射线衍射(XRD)分析镀层的物相组成、晶粒大小和晶格畸变情况。使用显微硬度计对合金镀层的硬度进行了测试。结果随着镀液中钨酸钠浓度的增大或者柠檬酸浓度的减小,镀层中的钨含量提高,晶粒尺寸减小,维氏硬度增大。热处理氛围对镀层硬度的影响不大,但会改变镀层微观形貌,镀层硬度随热处理温度先增大后减小,也随保温时间先增大后减小。结论当镀液中含有钨酸钠45 g/L,柠檬酸45 g/L,电镀完成后将镀层在400℃氩气保护下热处理1.5 h,得到的镀层是以镍为溶剂、钨为溶质的置换型固溶体Ni_(17)W_3,其具有表面平整、无裂纹,硬度达894HV0.1的优良性能。
[Abstract]:Objective to investigate the effects of citric acid concentration, sodium tungstate concentration and heat treatment process on the tungsten content, hardness, micromorphology and phase composition of Ni-W alloy coating. Methods Ni-W alloy coatings were prepared by electrodeposition of low carbon steel in different composition bath, and then treated by different heat treatment. Scanning electron microscopy (SEM) and its own EDS energy spectrum were used to observe the microstructure of the coating and to detect the tungsten content of the coating. The phase composition, grain size and lattice distortion of the coating were analyzed by X-ray diffraction (XRD). The hardness of alloy coating was tested by microhardness tester. Results with the increase of sodium tungstate concentration or the decrease of citric acid concentration, the tungsten content, grain size and Vickers hardness increased. Heat treatment atmosphere has little effect on the hardness of the coating, but it will change the microstructure of the coating. The hardness of the coating increases first and then decreases with the heat treatment temperature, and then decreases with the holding time. Conclusion when the bath contains sodium tungstate 45 g / L and citric acid 45 g / L, the coating is annealed in argon atmosphere at 400 鈩，

本文编号：2101616