人造金刚石表面化学镀Ni-Mo-P三元合金实验研究

发布时间：2018-01-11 15:27

  本文关键词：人造金刚石表面化学镀Ni-Mo-P三元合金实验研究　出处：《辽宁科技大学》2015年硕士论文　论文类型：学位论文

  更多相关文章： 化学镀 镀层 人造金刚石

【摘要】：人造金刚石具有超高硬度、高导热率、低摩擦系数等诸多优良性质,它广泛应用于工业生产中。但利用人造金刚石制造的工具在使用时存在一些问题。由于金刚石与胎体之间有较高的界面能,两者不能很好地浸润,使得工具的使用寿命大打折扣。此外,人造金刚石的耐热性不高,高温下易氧化失重或石墨化。目前主要解决方法是利用化学镀技术使人造金刚石表面金属化,使镀覆后的金刚石与胎体能够牢固结合,同时提高了人造金刚石的抗氧化性、热稳定性、耐磨性等特性。常用的金属镀层包括Ni-P、Ni-B等二元金属镀层,随着科技的快速进步,传统的二元金属镀层已经不能满足工业发展的需要。本文在化学镀Ni-P的基础上,进行工艺优化改进,引入了在高温下强度高、硬度高、膨胀系数低、耐蚀性好的金属钼(Mo),在金刚石表面形成高硬度,孔隙少,高耐蚀性等特点的Ni-Mo-P合金镀层。对人造金刚石粉体首先进行除油、粗化、敏化、活化、解胶等预处理,并选择合适的主盐和添加剂配制镀液,然后对人造金刚石粉体进行化学镀,最终获得表面镀覆有Ni-Mo-P合金镀层的粉体。镀层致密均匀,粉体包覆严实,具有金属光泽。其次,采用正交实验的方法,结合镀层镀覆效果及沉积速度,确定了人造金刚石粉体化学镀Ni-Mo-P合金镀层的最佳施镀方案:钼酸钠浓度为0.8/L,硫酸镍浓度为25g/L,次亚磷酸钠浓度为29g/L,十二烷基硫酸钠浓度为0.1g/L,氟化钠浓度为1.5g/L,pH为4.5,温度为86℃。络合剂用量为28 g/L,镀覆时间为1.5h。利用扫描电子显微镜(SEM)、能谱仪(EDS)的检测方法,分析镀层的表面形貌、镀覆效果、镀层成分;用激光粒度仪对镀覆后的人造金刚石粉体的粒度进行检测,粒径分布集中,粉体各项性能较好;进行了高温煅烧实验,实验结果显示表面镀层能够提高金刚石的耐热性。通过理论研究、施镀工艺优化及测试分析表明:人造金刚石表面镀覆Ni-Mo-P合金镀层理论和工艺可行,镀层性能良好,降低了应用成本,提高了人造金刚石的使用寿命。得到的施镀原理与施镀工艺丰富了新型多元化合金镀层的发展,为人造金刚石表面镀覆Ni-Mo-P合金镀层的工业化应用提供了理论依据和技术支持。
[Abstract]:Synthetic diamond has many excellent properties, such as high hardness, high thermal conductivity, low friction coefficient and so on. It is widely used in industrial production, but there are some problems in the use of synthetic diamond tools. Because of the high interfacial energy between diamond and matrix, they can not be well infiltrated. Besides, the heat resistance of synthetic diamond is not high, and it is easy to be oxidized or graphitized at high temperature. At present, the main solution is to use electroless plating technology to metallize the surface of synthetic diamond. The coated diamond can be firmly bonded with the matrix, and the oxidation resistance, thermal stability and wear resistance of the synthetic diamond are improved. The commonly used metal coatings include Ni-P. With the rapid progress of science and technology, the traditional binary metal coating, such as Ni-B, can no longer meet the needs of industrial development. Based on the electroless plating of Ni-P, the process optimization is carried out in this paper. The high hardness, high hardness, low coefficient of expansion and good corrosion resistance of molybdenum are introduced at high temperature to form high hardness and less porosity on diamond surface. Ni-Mo-P alloy coating with high corrosion resistance. The synthetic diamond powder was first treated with deoiling, coarsening, sensitization, activation and gel decomposition, and the appropriate main salt and additives were selected to prepare the bath. Then the synthetic diamond powder is electroless, and the powder coated with Ni-Mo-P alloy coating is obtained. The coating is dense and uniform, and the powder has metallic luster. By means of orthogonal experiment, combined with coating effect and deposition speed, the optimum plating scheme of Ni-Mo-P alloy coating for synthetic diamond powder electroless plating was determined: the concentration of sodium molybdate was 0.8 / L. Nickel sulfate concentration is 25 g / L, sodium hypophosphite concentration is 29 g / L, sodium 12 alkyl sulfate concentration is 0.1 g / L, sodium fluoride concentration is 1.5 g / L, pH is 4.5 g / L. The temperature was 86 鈩，

本文编号：1410126