Research on High Performance Surface Modified Layer with Dispersed Fine Particles

点击翻译按钮获取中文摘要

In order to improve the tribological performance of surface modified layer, dispersed particles, dispersed precipitations and ceramics particles spraying were investigated.1. Roller and ring/disk tests were carried out under non-lubricating condition in high vacuum to investigate the tribological performance of particle dispersed composite platings. The influence of elastic modulus of dispersed particles on stresses was investigated with FEM analysis. The maximum values of Von Mises stress in the plated layer increased with increasing particle content and with decreasing elastic modulus of particles. The wear behavior obtained in the experiment could be well explained by the calculated stress field.2. The rolling contact fatigue of a sprayed alumina ceramics was studied with a two-roller test apparatus with oil lubricant. The subsurface shear stresses were calculated with two-dimensional FEM analyses. The maximum values of orthogonal shear stress and maximum shear stress occurred withi … More n the sprayed layer. The depths of observed subsurface cracks were generally deeper than those of the maxima of shear stresses.3. The friction and wear characteristics of stainless steel with dispersed precipitations were investigated with ring-on-disk test apparatuses under oil lubricating condition and non-lubricating condition in air and in vacuum. The friction and wear performances of stainless steel were improved by dispersed precipitations.4. A gear test and a two-cylinder test were carried out under non-lubricating condition in high vacuum. In case of the Ni-P plated gear with dispersed PTFE particles, the wear was almost uniform along the tooth profile and the fluctuation of the dynamic load was small. Though the wear in the two-cylinder test was much smaller than that in the gear test, there is a good correlation of the average friction coefficients between the two tests.These results were useful to design the optimum thickness and dispersed particles of surface modified layer. Less