非调质钢C38N2Φ170mm热轧材连续冷却转变的研究  

A Study on Continuous Cooling Transformation of Φ170 mm Hot-Rolled Products of Non-Quenching-and-Tempering Steel C38N2

作　　者：文成[1] 蒋波[1] 杨忠[2] 王海龙 刘雅政[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]西宁特殊钢集团有限责任公司,西宁810005

出　　处：《特殊钢》2014年第1期57-60,共4页Special Steel

摘　　要：采用热膨胀法和金相法,通过Gleeble-1500热模拟试验机试验研究了非调质钢C38N2(/%:0.38C,0.55Si,1.42Mn,0.011P,0.047S,0.03Nb,0.015Ti,0.022Al,0.020N)在冷却速度0.5~20℃/s时的动态(950℃,变形速率5 s^(-1),50%变形,冷却至室温)和静态(未变形,880℃冷却至室温)的连续冷却转变(CCT)曲线。结果表明,未变形时非调质钢C38N2当冷却速度0.5℃/s时为铁素体-珠光体组织,3.0℃/s时为贝氏体+铁素体-珠光体组织,>3.0~11℃/s时为贝氏体+马氏体组织,15℃/s时为马氏体组织;当冷却速度≤11℃/s时动态CCT的相变开始温度均大于静态CCT相变开始温度。The dynamic （ deforming 50% at 950 ℃ with deformation rate 5 s -1, cooling to ambient） and static （ non- deforming, 880 ℃ , cooling to ambient） continuous cooling transformation （CCT） curves with cooling rate O. 5 -20 ℃/s of non-quenching-and-tempering steel C38N2 （/% ： 0. 38C ,0. 55Si, 1.42Mn,0. 011P,0. 047S,0. 03Nb,0. 015Ti ,0. 022A1, 0. 020N） have been tested and studied with using Gleeble-1500 thermal simulation machine by thermal expansion dilation method and metallographic examination. Results show that for non-deforming steel, with cooling rate 0. 5 ℃/s, tile struc- ture of non-quenching-and-tempering steel C38N2 is ferrite-pearlite, as cooling rate is 3.0 ℃/s its structure is bainite ＋ ferrite-pearlite, with cooling rate 〉 3.0 - 11 ℃/s the steel has bainite ＋ martensite structure and with 15 ℃/s the structure of steel is martensite; as cooling rate ≤ 11 ℃/s, all the phase transformation initial temperature of dynamic CCT is larger than that of static CCT.

关 键 词：非调质钢C38N2 相变 连续冷却转变(CCT)曲线 

分 类 号：TG335.1[金属学及工艺—金属压力加工]