【作者】 高叔轩；

【导师】 刘贵昌；

【作者基本信息】 大连理工大学 ， 化学工程， 2004， 硕士

【摘要】 为了降低工艺温度，提高沉积速度，更好的解决化学复合镀中第二相颗粒在镀液及镀层中分散的均匀性问题，本课题将超声波引入到传统的施镀工艺中，首先对在超声波辅助下的化学镀工艺进行了研究，着重总结了超声波辅助下镍盐、次磷酸盐、稳定剂特别是络合剂等因素对化学镀镍沉积速度和镀层性能的影响规律，初步确定了超声波辅助下化学镀镍的镀液配方和工艺条件。 在此基础上，考察了化学复合镀Ni—P／SiC(硬性颗粒)、Ni—P／PTFE(软性颗粒)，Ni—P／SiC—PTFE三种工艺中超声波的作用，并通过电子显微镜观察、孔隙率实验、极化曲线测量等对超声复合镀层的表面形貌和镀层性能做了评价。 在SiC化学复合镀工艺的研究中，主要考察了超声作用、分散方法、SiC粒径、SiC加入量和表面活性剂等对镀层中SiC含量(vol％)及分散性的影响，确定了最佳施镀工艺。研究结果表明，在超声波辅助下，通过选择适当的镀液配方以及施镀工艺，可以使SiC粒子在镀层中得到更多、很好的分散，镀液稳定，沉积速度有所提高，镀层的耐蚀性能有明显改善。 对于软性颗粒PTFE化学复合镀工艺的研究表明，连续的超声作用使镀液中的聚四氟乙烯发生交联沉淀，并导致被镀件电位上升而停止施镀，为此，初步摸索出了阴极极化和间歇超声波辅助下相结合的化学复合镀Ni—P／PTFE的新方法。试验结果表明，采用该方法，PTFE在镀层中分布均匀，含量较高，镀层增水性较好，镀液稳定，沉积速度较高。 在对Ni—P／SiC—PTFE化学复合镀工艺研究中发现：当SiC的粒度接近或小于PTFE的粒径时，更有利于两种颗粒的同时复合。更多还原

【Abstract】 Electroless composite plating is the codeposition process of one or several solid particles with metallic coatings based on electroless plating. In order to accelerate plating rate, decrease the operating temperature and disperse the particles more uniformly, electroless composite plating process was studied in ultrasonic field at low temperature. First, the electroless plating process was established by investigating the effects of Ni, H2PO2, stabilizers, especially complex agents on the plating rate and coating’s properties.On the base of above research, the ultrasonic effects on electroless composite plating Ni -P/SiC, Ni-P/ Polytetrafluoroeyhylene(PTFE) and Ni-P/SiC-PTFE were studied. The coatings prepared by ultrasonic process were analyzed by scanning electron microscope(SEM) coating porosity Anodic polarization curves, etc.Through examining the factors of SiC electroless composite plating process, such as ultrasonic effects, dispersion method, content of SiC in plating solution and surfactant etc, on the SiC concentration (vol % ) and dispersing properties of coatings, the best process were developed. The results indicated that the Ni-P/SiC composite coatings presented better corrosion resistance and SiC particles dispersing at the aid of the ultrasonic.To the soft particles(PTFE) electroless composite plating process, the sequence ultrasonic operation can make PTFE coagulating, coursing the potential rising and preventing the plating process. However, the new method of cathodic polarization combining with intermittent plating at the aid of the ultrasonic can ensure a stable plating rate and uniform coatings.In the study of the Ni-P/SiC-PTFE electroless composite plating process, it was found that SiC and PTFE particles were codeposition easily if the radius of SiC is not bigger than that of PTFE particle.更多还原