1Cr11Ni2W2MoV钢持久性能机理分析及工艺改进

对540 MPa断裂时间小于100 h的真空感应炉冶炼+电渣重熔(Φ600 mm锭)+锻造成材工艺生产的90 mm×90 mm 1Cr11Ni2W2MoV钢分析表明：钢中回火马氏体组织含量不足及马氏体板条间碳化物析出不均匀是导致钢材强度及韧性偏低进而导致持久性能断裂时间小于100 h的原因，通过将锻坯加热温度由1130～1150℃降低到1000～1020℃,锻造90 mm×90 mm钢材的锻造方式由一火次成材变为两火次成材，终锻温度≥900℃,持久性能试样的回火温度由660～680℃降低到600～620℃,使1Cr11Ni2W2MoV钢540 MPa持久性能断裂时间从36～37 h提高到146～148 h。

Mechanism Analysis and Process Improvement of 1Cr11Ni2W2MoV Steel Durability Performance

According to the analysis on 90 mm x 90 mm 1Cr11Ni2W2MoV steel with 540 MPa endurance rupture time less than 100 h produced by vacuum induction furnace smelting + electroslag remelting (Φ600 mm ingot) + forging material process, it is found that insufficient tempered martensite content in the microstructure and uneven carbide precipitation in the martensite lath are the reasons for the low strength and toughness of the steel, which leads to the durability and fracture time of less than 100 h. By decreasing the heating temperature of forging bloom from 1 130-1 150 °C to 1 000-1 020 °C , and changing forging method for 90 mm x 90 mm steel bar from once heating-forging to double heating-foring to ensure the end forging temperature >900 °C , and decreasing the tempering temperature of the durability test specimen from 660-680 °C to 600-620 °C , the fracture time of 540 MPa durability of 1Cr11Ni2W2MoV steel is increased from 36-37 h to 146-148 h.