WC-12Ni硬质合金粉体粒径及固含量对表面化学镀Ni-MoS_(2)复合层的影响  

Effect of particle size and solid content of WC-12Ni cemented carbide powders on the electrolessly coated Ni-MoS_(2) composite layer

作　　者：闫佳伟 姜淑文 王晋枝 柳鸣 YAN Jiawei;JIANG Shuwen;WANG Jinzhi;LIU Ming(School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China)

机构地区：[1]大连工业大学纺织与材料工程学院,辽宁大连116034

出　　处：《大连工业大学学报》2021年第5期345-352,共8页Journal of Dalian Polytechnic University

基　　金：国家自然科学基金项目(51601027);辽宁省自然科学基金项目(2019-ZD-0286).

摘　　要：为了研究颗粒粒径以及固含量对WC-12Ni粉体表面化学复合镀Ni-MoS_(2)层的影响及作用机制,对商用WC-12Ni粉体筛分得到3种不同粒径范围(10~25μm、25~30μm和30~40μm)的粉体并在固含量分别为25、75、125 g/L的条件下进行化学镀包覆Ni-MoS_(2)复合层。采用场发射扫描电子显微镜(FE-SEM)和能谱仪(EDS)对镀覆前后WC-12Ni粉体的表面形貌、Ni-MoS_(2)层厚度以及元素分布进行表征,并对粉体表面复合镀层的均匀性、致密性和完整性进行评价。结果表明,无论何种粒径分布的WC-12Ni粉体,增加待镀粉体在镀液中的固含量均有利于提高其表面Ni-MoS_(2)复合镀层的均匀性、致密性和完整性;当镀液中粉体固含量较低时,只有尺寸较大的WC-12Ni颗粒(25~30μm和30~40μm)表面能获得均匀致密的Ni-MoS_(2)镀层,尺寸分布为10~25μm的细小WC-12Ni颗粒表面镀覆不均匀、甚至有一定比例未包覆粉体。镀液中固含量的增加提高了WC-12Ni颗粒之间在机械搅拌时发生碰撞、剪切和摩擦等相互作用的概率,而粉体粒径增加使得颗粒之间的相互作用更加强烈,均有利于Ni-MoS_(2)复合镀层在颗粒表面的均匀沉积和致密化。The effect of particle size and solid content on the electroless composite Ni-MoS_(2) layer on the surface of WC-12Ni powders and the influence mechanism have been investigated.Three powders with different particle size ranges(10-25μm,25-30μm and 30-40μm)were obtained by sieving commercial WC-12Ni powders and the electroless composite Ni-MoS_(2) deposition was carried out under the solid contents of 25,75,125 g/L respectively and the surface morphology,Ni-MoS_(2) layer thickness and element distribution of WC-12Ni powders before and after plating were characterized by field emission scanning electron microscope(FE-SEM)and energy dispersive spectrometer(EDS)and the uniformity,compactness and integrity of the composite coating on the powder surface were evaluated.The results indicated that the increase of the solid content of WC-12Ni powders in the plating solution was beneficial to improve the uniformity,compactness and integrity of the Ni-MoS_(2) composite coating on the surface,without considering the particle size distribution of WC-12Ni powder.When the powder solid content in the plating bath was low,a uniform and dense Ni-MoS_(2) coating can only be obtained on the surface of WC-12Ni particles with the larger sizes(25-30μm and 30-40μm).The surface of fine WC-12Ni particles with a size distribution of 10-25μm is not uniformly coated,and even there are a certain proportion of uncoated powders.The probability of interaction between the WC-12Ni particles such as collision,shear and friction was improved by the increase of solid content as well as the increase of particle size in the plating bath,which aided to the uniform deposition and densification of the Ni-MoS_(2) composite coatings on the surface of the WC-12Ni particles.

关 键 词：硬质合金粉体 化学镀 二硫化钼 

分 类 号：TB333[一般工业技术—材料科学与工程]