Effects of activated sintering process on properties and microstructure of W-15Cu alloy

Abstract

The effects of activated sintering technology of H₂ atmosphere sintering on the microstructure and properties of W-15Cu alloy using ultrafine W-15Cu composite powder fabricated by spray drying & calcining-continuous reduction technology were investigated. The experimental results showed that W-15Cu alloy, consolidated by activated sintering technology of H₂ atmosphere sintering for 1 h at 1300 °C, with 98.5 % relative density, transverse rupture strength 1218 MPa, Vickers hardness HV0.5 378, average grain size about 1.2 μm and thermal conductivity 192 W/m·K, was obtained. In comparison to the normal sintering process, activated sintering process to W-15Cu alloy could be achieved at lower sintering temperature. Furthermore, better properties in activated sintered compacts were obtained, and activated sintering process resulted in finer microstructure and excellent properties.

Keywords

ultrafine composite powder / W-15Cu alloy / activated sintering process / microstructure / properties

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