Abstract:Ultra-fine Mo-30Cu composite powders with grain size of 17−50 nm were fabricated by sol-spray drying, calcination and subsequent hydrogen reduction process. The results show that the influence of sintering temperature, time and the oxygen content in the powder on sintering densification were investigated. Meanwhile the tensile mechanical property of alloys was examined, and the tensile fracture surface features of the alloys were analysed. The results show that the reduction temperature has a great impact on powder morphology; the rapid densification can be realized in those green compacts, which are sintered in the temperature range of 1 050−1 200 ℃; when they are sintered at 1 050 ℃ for 60 min in H2 atmosphere, the relative density can achieve 99%, and their grains are fine, and the microstructures are homogeneous. The maximum tensile strength and elongation rate of the alloy are 755 MPa and 6.41%, respectively.

Key words: Mo-Cu alloy; ultra-fine powders; mechanical property; fracture mechanism