Ni—W—P—SiC复合镀层与氮碳共渗复合强化的组织与结构研究

本文讨论工艺条件对Ｎｉ－Ｗ－Ｐ－ＳｉＣ复合镀层表面形貌的影响，分析复合镀层的截面显微组织以及镀层的相结构。结果表明，复合镀层的表面形貌与镀液的ｐＨ值和阴极电流密度有很大关系；复合镀层经氮碳共渗后，增强镀层与基体金属之间的结合力，使其由机械结合转变成冶金结合；Ｘ射线衍射表明复合镀层在镀态下的为非晶态，经氮碳共渗后转变为晶态，并产生很多新相。这些相的存在提高了复合镀层的硬度及耐磨性。

MICROSTURCTURE OF COMBINING STRENGTHENING OF Ni-W-P-SiC COMPOSITE COATING AND NITROCARBURIZING

Effects of plating conditions on the surface morphologies of Ni-W-P-SiC composite coatings are discussed , and microstructures of cross section and phase structures of the coatings are also analyzed. The results show that the surface morphologies of the deposits are greatly related to the pH values of bath and cathodic current density . The joint form between the coating and matrix increases and it changes from mechanical joint metallurgical joint after nitrocarburizing . X-ray diffraction displays that the composite coatings are amorphous as plated status, but they change into crystal, separating out a lot of phases when nitrocarburized. The existence of there new phases increases the hardness and wear resistance of the composite coatings.