材料科学与工程学报2017，Vol.35Issue(3)：358-362,379,6.DOI:10.14136/j.cnki.issn1673-2812.2017.03.003
石墨的添加对NiCr-W-Ti自润滑复合材料高温摩擦学性能的影响
Effects of Graphite Addition on Tribological Properties of NiCr-W-Ti Self-lubricating Composites at Elevated Temperatures
摘要
Abstract
NiCr-W-Ti self-lubricating composites were fabricated by mechanical alloying and hot-pressing sintering.Ni20Cr alloy was taken as the matrix of the composites;meanwhile,W,Ti and graphite were added to it,and the influences of different amount of graphite on the microstructure and tribological properties of the composites at elevated temperatures were studied.The friction and wear properties of the composites sliding against AlO3 ceramic ball were evaluated on a UMT-3 high-temperature tribometer with a ball-on-disc configuration.The microstructure and worn surfaces of the composites before and after friction test were observed and analyzed by Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD).Results show that the NiCr-W-Ti composite with the addition of 3wt.％ graphite exhibits the best comprehensive properties of mechanics and tribology.When testing temperature below 300℃C,the effective tribo-film has not formed on the worn surfaces,which leads to high wear rate.When temperature higher than 500℃C,oxides can be found in the friction layer and the worn surfaces were covered by a lubricating film composed of smooth oxides,which effectively protect the worn surface and contribute to the wear rate decreasing.关键词
Ni20Cr合金/摩擦层/摩擦氧化物/摩擦磨损性能Key words
powder metallurgy method/self-lubricating composites/tribological properties/wear mechanisms分类
机械制造引用本文复制引用
汪建义,陕钰,王文珍,贾均红..石墨的添加对NiCr-W-Ti自润滑复合材料高温摩擦学性能的影响[J].材料科学与工程学报,2017,35(3):358-362,379,6.基金项目
自然科学基金资助项目(50972148,51471181,51175490) （50972148,51471181,51175490）
