摘要
以Cr质量分数为3.7%,4.5%的铁道车辆用高强高耐候钢为研究对象,在DIL805A热膨胀仪上进行焊接热影响区连续冷却转变实验,研究不同条件下实验钢组织转变与硬度变化的规律。结果表明:Cr质量分数为3.7%的1#实验钢发生了铁素体、珠光体、贝氏体与马氏体转变,而Cr质量分数为4.5%的2#实验钢只发生了贝氏体与马氏体转变;Cr质量分数从3.7%增加至4.5%时,实验钢相变点明显右移,铁素体和珠光体转变消失,且马氏体开始转变温度降低;同一条件下,2#实验钢硬度值较大,且在为10℃/s时由于V析出的影响出现波谷;1#实验钢在冷却速度≤0.5℃/s时可获得综合性能较好的组织,而2#实验钢需通过焊后热处理才能获得理想的组织。
Taking high strength and weathering steel for railway vehicles with Cr mass fraction of 3.7% and 4.5% as the research object, experiments of continuous cooling transformation in the welding heat affected zone were carried out on the DILS05A thermal expansive apparatus. Laws of microstructure transformation and hardness change of tested steels under different cooling rates were studied. The results show that the ferrite, pearlite, bainite and martensitic transform occurs in the No. 1 tested steel with Cr mass fraction of 3.7%, whereas only bainite and martensite transformation occurs in the No. 2 tested steel with Cr mass fraction of 4.5%. When mass fraction of Cr increases from 3.7% to 4.5%, the phase transition point of the tested steel significantly shifts to the right, the ferrite and pearlite transformation are disappeared and the starting transition temperature of martensite decreases; the hardness of No. 2 tested steel is larger at the same cooling rate, and a wave valley occurs due to the influence of V precipitation at a cooling rate of 10℃/s. The No. 1 tested steel can obtain a better comprehensive structure when the cooling rate is less than or equal to 0.5℃/s, but the No. 2 tested steel needs heat treatment after welding to achieve desired microstructure.
作者
胡学文
张建
张海涛
闫军
潘红波
吴保桥
潘烁
HU Xucwen;ZHANG Jian;ZHANG Haitao;YAN Jun;PAN Hongbo;WU Baoliao;PAN Shuo(School of Materials and Engineering,University of Science and Technology Beijing,Beijing 100083;Technology Center,Ma＇anshan Iron and Steel Co.Ltd.,Ma＇anshan243000,China;a.Schoolof Metallurgical Engineering,b.Key Laboratory of Metallurgical Emission Reduction and Resources Recycling of Ministry of Education,c.Anhui Province Key Laboratory of Metallurgical Engineering and Resources Recycling,Anhui University of Technology,Ma＇anshan 243002,China)
出处
《安徽工业大学学报（自然科学版）》
CAS
2018年第2期110-114,共5页
Journal of Anhui University of Technology（Natural Science）
基金
安徽省重大专项项目(15czz02036)
安徽省高校自然科学研究资助项目(KJ2016A091)
关键词
铁道车辆
高强高耐候钢
连续冷却转变
焊接
railway vehicle
high strength and weathering steel
continuous cooling transformation
welding
