Abstract:Tungsten heavy alloys (90W-6Ni-4Mn) were prepared through spark plasma sintering (SPS) using micron-sized W, Ni, and Mn powders without ball milling as raw materials. The effects of sintering temperature on the microstructure and mechanical properties of the 90W-6Ni-4Mn alloys were investigated. SPS technology was used to prepare 90W-6Ni-4Mn alloys with relatively high density and excellent comprehensive performance at 1150-1250 °C for 3 min. The 90W-6Ni-4Mn alloys consisted of the W phase and the γ-(Ni, Mn, and W) binding phase, and the average grain size was less than 10 μm. The Rockwell hardness and bending strength of alloys first increased and then decreased with increasing sintering temperature. The best comprehensive performance was obtained at 1200 °C, its hardness and bending strength were HRA 68.7 and 1162.72 MPa, respectively.

Key words: 90W-6Ni-4Mn alloy; spark plasma sintering; microstructure; Rockwell hardness; bending strength