Effect of Milling Time on the Properties of Nanocrystalline CuCr50 Alloys
Nanocrystalline CuCr50 alloys were fabricated by means of mechanical alloying and spark plasma sintering. The influence of milling time on the as-milled powders and properties of sintered compacts were investigated. The results show that crystallite size of powders decreases gradually with increase of milling time, while the micro-strain increases firstly then decreases correspondingly. The crystallite size is 22 nm at milling 100h.The micro-hardness of the compacts improves greatly with the increase of milling time, reaching 363HV at 150h which is about 3 times as high as that of the industrial standard (120HV), while the electrical conductivity improves gradually decline. The bulk nanocrystalline CuCr50 alloys sintered at 900°C for 5min exhibit high relative density of 96% and uniform microstructure: nanoparticles Cr with size of about 120nm are uniformly dispersed in the matrix.
Jianzhong Wang and Jingang Qi
K. Y. Shi et al., "Effect of Milling Time on the Properties of Nanocrystalline CuCr50 Alloys", Advanced Materials Research, Vols. 299-300, pp. 824-827, 2011