【摘要】 镍铝金属间化合物是一种新的高温材料,应用前景十分广泛^[1]。在镍铝金属间化合物中添加合适的高温润滑剂,可制备出性能良好的高温自润滑摩擦材料。本实验采用粉末冶金工艺,在镍铝粉末中添加不同含量的石墨（G）,制备出Ni-Al-G摩擦材料,通过电子显微镜、X射线衍射仪、电子天平称、摩擦磨损实验机等仪器分析了试样的表面相貌、组织结构、孔隙率、摩擦性能。实验结果表明:当添加石墨含量逐渐增加时,Ni-Al-G摩擦材料孔隙率下降,硬度不断下降。石墨粒径较小,在与镍铝反应生成额外新的产物Ni₃AlC_0.5,起到固溶强化和细晶强化的作用。随着石墨含量的升高,Ni₃Al基材料摩擦系数先缓慢下降,后逐渐升高,在石墨含量为3%时性能最佳。更多还原

【Abstract】 Nickel-aluminum intermetallic compound is a new high-temperature material and has application of a wide range of prospects.High-temperature self-lubricating materials with good performance can be produced by the means of adding appropriate high-temperature lubricants to the nickel-aluminum intermetallic compounds.An experiment of producing Ni-Al-G friction material was carried out by adding different content of graphite （g） into the nickel-aluminum powder.The surface morphology,structure,Porosity and hardness of the Ni-Al-G alloy specimen were analyzed by means of optical microscope,X-ray diffractometer and hardness analysis.The results showed that:with the gradual increase of the graphite content the theoretical density of intermetallic compounds decreased while the porosity increased,the hardness decreased.The reason is that graphite particle is small,with a new nickel-aluminum reaction product Ni₃Al,and Ni₃Al play the role of solid solution strengthening and fine grain strengthening.With the increase of graphite content,the friction coefficient of Ni₃Al-based materials decreased slowly at first and then increased gradually.The effect of graphite on the friction properties of Ni₃Al-based materials is not obvious.It varies in a certain range and has the best performance when the content of graphite is about 3%.更多还原