Abstract: The effect of two-pass defonnation-first pass 60% , 20 s^-1, second pass 20% , 10 s^-1 at 850〜1 050 ℃ and different holding time (10 ~ 50 s) between passes on recrystallization of Nb microalloying low carbon bainitic steel (0. 21C, 1. 50Cr, 0. 20Mo, 0. 047Nb) and the interaction between thermal-deformed austenite recrystallization and strain- induced precipitation of Nb( CN) have been studied by Gleeble-2000 thermal simulation test machine. Results showed that with defonnation of steel at 1 000 ~900  ℃ for 10 s, the strain-induced precipitation of Nb (CN) began to delay austenite recrystallization process； and ≤10 μm austenite grain size could be got by two-pass deformation.

摘要： 通过Gleeble-2000热模拟试验机研究了 850 ~ 1 050 ℃双道次变形(第1道次60% ,20 s^-1,第2道次 20%,10 s^-1)及不同道次间隔时间(10-50 s)对含铝低碳贝氏体钢(％ ：0. 21C、1. 50Cr、0. 20Mo、0. 047Nb)再结晶的 影响和应变诱导析出Nb(CN)与热变形奥氏体再结晶的相互作用。结果表明,该钢在1 000 - 900  ℃变形10 s后，开始应变诱导析出Nb(CN),延迟静态再结晶过程;通过双道次变形,可获得≤10 μm奥氏体晶粒。