Effect of forging temperature on microstructure and mechanical properties of powder hot-forged alloy contained molybdenum

Fe-1C-2Cu-xMo (x=0.50, 0.85, 1.46, mass fraction) alloys were fabricated by powder hot-forging in this paper. The effect of forging temperature and Mo content by mass on the density, microstructure, static mechanical properties, and dynamic friction properties of the alloys were investigated. In the results, the forging can effectively increase the density of alloys, and the relative density can reach 98.5% after forging. The microstructure is mainly composed of bainite, martensite, and retained austensite. The hardness of alloys increases with the increase of Mo content, and decreases first and then increases with the increase of forging temperature. The hardness of Fe-1C-2Cu-1.46Mo alloys forged at 1050 ℃ reaches the maximum value of HRB 116.38. The transverse rupture strength is jointly affected by the Mo content by mass and forging temperature, the maximum strength of Fe-1C-2Cu-0.50Mo alloys forged at 1000 ℃ can reaches 2608 MPa, and the fracture mode of alloys is the mixture of ductile and brittle fracture. As the increase of Mo content, the dynamic friction properties increase significantly. The friction coefficient of Fe-1C-2Cu-1.46Mo alloys forged at 950 ℃ is only 0.088, which is obviously lower than that of others with the smaller fluctuation.