【作者】 潘文；

【导师】 张一兵；

【作者基本信息】 武汉理工大学 ， 机械设计及理论， 2006， 硕士

【摘要】 本文基于把软金属润滑剂熔浸到金属陶瓷粉末冶金材料的孔隙中制各自润滑发汗体的方法,建立了一种自润滑发汗体结构模型,探讨发汗体的结构参数,软金属润滑剂的物理性质以及外界条件对其浸渗和扩散的影响。本文的主要研究工作分为以下几个部分: 1) 基于高强圆柱发汗体,提出一种填充计算模型,研究了圆柱发汗体内圆球颗粒的排列方式及其相对大小对孔隙率的影响,给出了圆柱发汗体和圆球颗粒半径比R/r与孔隙率ε的关系曲线,以及圆柱发汗体高和圆球颗粒直径比H/2r与孔隙率ε’的关系曲线,分析结果发现:当R/r和H/2r的值分别大于一定值时,圆柱体试件的孔隙率将趋于稳定值。论文根据圆柱发汗体填充模型分析结果,给出了圆柱体发汗体试件的最小尺寸和推荐尺寸的计算方法。 2) 对采用自发熔融浸渗法将软金属润滑剂渗入金属陶瓷基体材料的过程进行了理论研究,以液态Sn为例分析了润湿角,表面张力,温度条件等对浸渗过程的影响。润湿角小于90°时可以实现自发浸渗,当润湿角大于90°时则需要外加压力才能浸渗。 3) 利用渗流理论对自润滑发汗体的渗透率、孔隙率和润滑剂熔体的粘度对发汗体的扩散特性的影响进行了研究,得出在相同温度和压力梯度下,Sn,Pb,Ag在发汗体内的流动量由大到小依次排列。更多还原

【Abstract】 The dissertation is based on the method that preparing self-lubricating sweat-sinter by infiltrating liquid soft metal lubricator into the cermet, building a structural model of self-lubricating sweat-sinter, studying the effect of structural parameters of sweat sinter, physics character of soft metal lubricator and working condition on lubricant’s infiltrating and diffusing. The main research work is divided into following parts:1. Based on self-lubricating columned sinter with high strength, a filling model has been set up, the effects of arrange style and the relative size between cylinder and ball granule on porosity have been studied, the relative curve between the radius ratio of cylinder to granule(R/r) and porosity(e) and the relative curve between the ratio of cylinder’s height to granule’s diameter(H/2r) and porosity(e’) have been drawn. The results show that porosity trends to a steady value when R/r and H/2r reach to certain values. Based on the analysed results of columned sinter filling model, the calculational methods of minimum size and recommended size of columned sweat-sinter have been given.2. The process that the liquid soft metal lubricator infiltrating into the cermet was sturied by infiltration method, and the effects that the wetting angle, the surface tension of liquid Sn, the temperature, and the pressure on the infiltrating process were analysed. The melt infiltration can be taken spontaneously when the wetting angle is below 90°, but it needs outer pressure when the wetting angle is above 90°.3. Using seepage theory, the effects that the permeability and porosity of sweat-sinter, and the wikipedia of liquid lubricant on the diffusing characteristic were studied. The result showed that the flux of Pb, Sn and Ag under the same temperature and pressure grads is decreased in turn.更多还原