2Cr12Ni4Mo3VNbN钢的冲击性能

Impact Property of 2Cr12Ni4Mo3VNbN Steel

将不同炉次的2Cr12Ni4Mo3VNbN钢锭锻造成ϕ220 mm棒材。对棒材进行1050℃保温1 h油淬、560℃回火2 h空冷和540℃回火2 h空冷。棒材的冲击试验表明,钢锭顶部和底部锻制的棒材冲击性能差异较大。为此,检测了由两炉次钢锭锻制的2Cr12Ni4Mo3VNbN钢棒材的冲击韧度、冲击断口形貌、化学成分、显微组织和析出相成分。结果表明:钢锭顶部和底部锻制的2Cr12Ni4Mo3VNbN钢棒材中一次MX型析出相的含量和分布不同,从而导致其冲击性能差异较大。

Different heats of 2Cr12Ni4Mo3VNbN steel ingots were forged into bars 220 mm in diameter.The bars were oil quenched from 1050℃,first tempered at 560℃for 2 h and air cooled,and secondly tempered at 540℃for 2 h and air cooled.From impact test for the bars it was seen that the bars forged from top and bottom of the ingots exhibited more significant difference in impact property.For this reason,2Cr12Ni4Mo3VNbN steel bars forged from two heats of ingots were tested for impact toughness,pattern of impact fracture,chemical composition,microstructure and composition of precipitated phase.The results showed that the 2Cr12Ni4Mo3VNbN steel bars forged from top and bottom of the ingot differed in amount and distribution of primary MX type precipitated phase,thus resulting in more significant difference in their impact property.