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在碱式碳酸镍溶液中获得了纳米晶结构Ni-Mo合金,利用扫描电子显微镜(SEM)、X射线衍射(XRD)等技术对镀层结构进行分析,结果表明,镀层由Ni Mo和β-Ni4Mo两相组成,晶粒尺寸约为23.2nm。Ni Mo合金固溶体呈(111)晶面择优取向;β-Ni4Mo固溶体表现为较强的(200)晶面择优取向。电沉积参数对镀层外观、表面形貌和结合力有较大影响,当镀液pH值10.0左右,温度为30～35℃,电流密度为2～5A/dm2时,可以获得镀层外观质量和结合力良好的Ni-Mo合金镀层。镀液钼酸盐浓度增大,镀层中含钼量增加,镀层硬度先增加后下降,在钼酸盐浓度为8～12g/L时硬度最高,镀层强化主要为固溶强化所致。镀液中钼酸盐和氨水浓度影响镀层内应力。
The nanocrystalline Ni-Mo alloy was obtained in basic nickel carbonate solution. The structure of the coating was analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the coating consists of Ni Mo and β-Ni4Mo Two-phase composition, grain size of about 23.2nm. The solid solution of Ni Mo alloy shows the preferred orientation of (111) crystal plane. The β-Ni4Mo solid solution shows a strong preferred orientation of (200) crystal plane. Electrodeposition parameters have great influence on the appearance, surface morphology and bonding force of the coating. When the bath pH value is about 10.0, the temperature is 30 ~ 35 ℃, the current density is 2 ~ 5A / dm2, the coating appearance quality and the combination can be obtained Good Ni-Mo alloy coating. The concentration of molybdate in bath increases, the content of molybdenum in the coating increases, the hardness of the coating increases firstly and then decreases, and the hardness is the highest when the molybdate concentration is 8 ~ 12g / L. The strengthening of the coating is mainly caused by solid solution strengthening. The concentration of molybdate and ammonia in the bath affects the stress in the coating.