粉末锻造Fe–Ni–Cu–C–Mo齿轮材料热处理及性能研究

对Fe–Ni–Cu–C–Mo粉末锻造材料的锻后热处理工艺进行了研究，通过动态连续冷却转变试验绘制出该材料的连续冷却转变（continuous cooling transformation，CCT）曲线，指导材料锻后冷却工艺的选取。对Fe–Ni–Cu–C–Mo淬火试样进行不同温度的低温回火试验，探究不同回火温度对该材料微观组织与力学性能的影响。结果表明，当锻后冷却速率大于7.0 ℃·s?1时，Fe–Ni–Cu–C–Mo粉锻材料组织全为马氏体，硬度趋于稳定；在150 ℃和175 ℃回火，碳化物均匀地分布在马氏体板条内部，起到析出强化的作用，材料表现出优异的抗拉性能。

Heat treatment and properties of powder forged Fe-Ni-Cu-C-Mo gear materials

The heat treatments of the powder forged Fe?Ni?Cu?C?Mo materials after forging were studied. The continuous cooling transformation diagram of the powder forged Fe?Ni?Cu?C?Mo alloys was constructed to guide the selection of cooling process after forging. The quenching Fe?Ni?Cu?C?Mo specimens were tempered at various temperatures in the low temperature tempering test, and the effects of tempering temperatures on the microstructure and mechanical properties of the Fe?Ni?Cu?C?Mo materials were investigated. The results show that, when the cooling rate of the Fe–Ni–Cu–C–Mo specimens after forging is more than 7.0 ℃·s?1, the microstructure is the martensite and the hardness tends to be stable. Tempering at 150 and 175 ℃, the carbide is evenly distributed inside the martensite lath, which acts as the precipitation strengthening, and the Fe–Ni–Cu–C–Mo specimens exhibit the excellent tensile properties.