机械活化热压制备新型Cu/Cr2Nb触头材料的组织与性能

The Microstructures and Properties of Novel-Type Cu/Cr2Nb Contact Materials Fabricated Mechanically Activated Hot-Pressing

摘要:

将Cu、Cr、Nb元素粉经25 h机械合金化活化处理后，在1000 ℃保温1 h的工艺下通过真空热压来制备新型Cu/Cr2Nb触头材料，研究了不同成分Cu/Cr2Nb触头材料的组织和性能。结果表明，在机械合金化过程中未能合成出Cr2Nb，但在热压过程中得到了充分合成和析出，所制备的Cu/Cr2Nb触头材料的组织均匀细小，Cr2Nb相尺寸在几个微米。当Cr2Nb含量(质量分数)为25%～35%时，Cu/Cr2Nb触头材料的致密度与熔渗法和热压法制备的常规CuCr50触头材料相当，但前者的硬度和电导率却明显高

Abstract:

Using Cu, Cr, Nb elemental powders activated by mechanical alloying (MA) for 25 h, the novel-type Cu/Cr2Nb contact materials were fabricated by vacuum hot-pressing at 1000 ℃ for 1 h. The microstructures and the properties of Cu/Cr2Nb contact materials with different compositions were investigated. The results show that Cr2Nb phase can not be synthesized during MA, but can be fully synthesized during vacuum hot-pressing. The prepared Cu/Cr2Nb contact materials have homogeneous and fine microstructures, and Cr2Nb phase sizes fall in several micro. The relative density of Cu/Cr2Nb contact materials with 25%~35% Cr2Nb is comparable with those of CuCr50 prepared by conventional or infiltrating process, but the hardness and conductivity of the former are obviously superior to those of the latter