35CrMo钢表面电火花沉积NiCr合金强化层特性的研究

Research on the Character of NiCr Coating Deposited on 35CrMo Steel by the Electro-spark Deposition

采用电火花沉积技术,以NiCr合金为堆焊电极,在35CrMo钢表面沉积NiCr合金强化涂层。用显微硬度计测试了涂层的显微硬度,用SEM,EDX,XRD等方法表征了涂层的微观结构、化学成分分布及相组成。结果表明:涂层的表面显微硬度约为基体的2倍;涂层与基体的主要元素发生了相互扩散,涂层是由基体与NiCr合金电极发生反应形成的冶金结合层,主要成分为NiCrFe和FeNi。

NiCr alloy coating was produced on the surface of 35CrMo steel with NiCr electrode by electro-spark deposition.The micro-hardness was obtained with hardness meter,the microstructure and chemical composition distribution and phase composition of the coating were investigated with scanning electron microscopy（SEM）,energy dispersion spectrum（EDX） and X-ray diffraction（XRD） respectively.The results show that the micro-hardness of the coating is about 2 times as that of the substrate.Inter-diffusion takes place and metallurgy combination layer forms between the coating and the substrate,the main phase composition of the coating consists of NiCrFe and FeNi.