摘要
测定了稀土脱氧和铝稀土复合脱氧钢焊接热影响区(HAZ)的连续冷却转变曲线,分析了2种钢中的夹杂物种类及其HAZ的显微组织和常温冲击韧性。得到如下结论:稀土脱氧使钢中主要夹杂物从Mn S转变为RE2O2S+Mn S,而铝稀土复合脱氧钢中夹杂物主要是Ce Al O3+Ce2S3+Mn S。稀土脱氧钢HAZ中能获得晶内铁素体的冷速较宽,约为0.5~7.5℃/s。铝稀土复合脱氧钢HAZ获得晶内铁素体组织较稀土脱氧钢要困难一些,适合晶内铁素体形成的冷速变窄为1~3℃/s,HAZ中晶内铁素体的含量明显低于稀土处理钢,Al脱氧弱化了稀土处理对钢HAZ组织的改善作用。焊接热输入线能量为100 k J/cm时,稀土脱氧能够明显改善钢HAZ的室温冲击韧性。
In this paper, the continuous cooling transformation curves of the welding heat affected zones （HAZ） were measured in steels deoxidized by rare earth （RE） and composite aluminum ＋ RE, respectively. The composition of inclusions and impact toughness of HAZ at room temperature were analyzed in the above-mentioned two steels. The obtained results were as follows： the main inclusions in the steel changed from binS to RE202S ＋ MnS after rare earth treatment,the composite aluminum ＋ RE deoxidation changed the inclusions into CeAI03 ＋ Ce2S3 ＋ MnS in C-Mn steel. The profitable cooling rate range for intragranular ferrite formation was wide during continuous cooling, about 0.5 - 7.5 ~C/s, in the HAZ of rare earth treated C-Mn steel. While in the aluminum ＋ RE deoxidized steel, the profitable cooling rate ranged for HAZ to obtain intragranular ferrite was narrow,only about 1 -3 ~C/s, meaning it was difficult for intragranular ferrite formation. The content of intragranular ferrite in the HAZ of RE killed steel was more than that in the HAZ of aluminum ＋ RE deoxidized steel, demonstrating that A1 deoxidation weaken the effect of RE deoxidization on the microstructure improvement of HAZ in steel. When welding heat input line energy was 100 kJ/cm, rare earth treatment in the steel could improve HAZ impact toughness at room temperature obviously.
作者
宋明明
宋波
薛正良
杨占兵
文彬
胡春林
SONG Mingming SONG Bo XUE Zhengliang YANG Zhanbing WEN Bin HU Chunlin(School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China The State Key Laboratory for Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China)
出处
《炼钢》
CAS
北大核心
2017年第5期24-30,共7页
Steelmaking
基金
国家自然科学基金资金资助项目(51274269)
国家自然科学青年基金资助项目(51604198)
关键词
氧化物冶金
异质形核
晶内铁素体
显微组织
钢的性能
oxides metallurgy
heterogeneous nucleation
intmgranular acicular ferritemicrostructure
steel performance
