热处理工艺路径对9Ni低温钢组织和性能的影响

对9Ni低温钢进行淬火＋回火（QT）、淬火＋淬火＋回火（QQT）不同工艺路径的热处理试验，分析了不同热处理工艺路径下9Ni低温钢组织和性能的影响。结果表明：不同的热处理工艺路径直接影响9Ni低温铜最终的性能。相较于淬火＋回火（QT）工艺路径，采用含有两相区淬火的QQT工艺能明显提高9Ni低温铜的低温韧性，但降低强度。在淬火＋回火（QT）工艺路径下，随着回火温度的升高，9Ni钢回火析出组织更加充分均匀，其低温韧性呈上升趋势。在淬火＋淬火＋回火（QQT）工艺路径下，9Ni钢的低温韧性随两相区淬火温度的升高呈下降趋势。

Influence of Heat Treatment on and Properties of Cryogenic Steel 9Ni

The different heat treatment as Quench and temper（QT）, quench and quench and temper（QQT） of 9Ni cryogenic steel was investigated. The results indicated that the final properties of 9Ni steel were strongly influenced by the path of heat treatment. Compared with quenching -~ tempering （QT） process, using contains two phase path of QQT quenching process area can obviously increase the cryogenic toughness of 9Ni steel, but reduces the intensity. In quenching ~ tempering （QT） process path, with tempering temperature elevatory, the tempering exhalation organization of 9Ni steel was more fully homogeneous, its cryogenic toughness shows ascendant trend. In quenching -~ quenching and tempering QQT） process path, the cryogenic toughness of 9Ni steel were downtrend with quenching temperature of two--phase region increases.