模拟焊后热处理对厚规格16MnDR钢板组织性能的影响
Effect of simulated post weld heat treatment on microstructure and properties of thick gauge 16MnDR steel plate
曲之国 1张万新 1白学飞 1王东明 1张友建1
作者信息
- 1. 日钢营口中板有限公司,辽宁 营口 115005;辽宁省中厚板专业技术创新中心,辽宁 营口 115005
- 折叠
摘要
对55 mm厚16MnDR正火态钢板进行590 ℃保温不同时间(135、405 min)的模拟焊后热处理,研究模拟焊后热处理对厚规格16MnDR钢板显微组织和力学性能的影响.结果表明,随模拟焊后热处理保温时间的增加,正火态钢板强度先增加后降低,但整体变化幅度不超过10 MPa;钢板厚1/4、1/2处的冲击吸收能量变化呈现不同的趋势,厚1/4处为单调降低,厚1/2处则先增加后降低.经模拟焊后热处理,16MnDR钢板的显微组织较正火态未发生显著变化,仍为铁素体+珠光体,但片层状渗碳体逐步向球状或点状渗碳体转变;此外,钢中析出碳化物数量随保温时间增加而增加,但长大趋势不明显,沿晶界的渗碳体析出是导致钢板冲击性能降低的主要原因.
Abstract
Simulated post weld heat treatment(PWHT)at 590 ℃ for different holding time(135,405 min)was conducted on a 55 mm thick 16MnDR steel plate as-normalized and the effect of simulated PWHT on the microstructure and mechanical properties of the plate was studied.The results show that as the holding time of simulated PWHT increases,the strength of the normalized steel plate increases first and then decreases,but the overall change amplitude does not exceed 10 MPa.The impact absorbed energy at 1/4 and 1/2 thickness of the steel plate shows different trends,which decreases monotonically at 1/4 thickness,while increases first and then decreases at 1/2 thickness.After the simulated PWHTs,there are no significant change in the microstructure of the steel plate compared to the normalized state,which remains ferrite+pearlite,but the lamellar cementite gradually transforms into spherical or punctate cementite.The number of precipitated carbides in the steel increases with the increase of holding time,but the growth trend is not obvious,and the precipitation of cementite along grain boundaries is the main reason for the reduction of impact absorbed energy.
关键词
厚规格16MnDR钢板/焊后热处理/组织/力学性能Key words
thick gauge 16MnDR steel plate/post weld heat treatment(PWHT)/microstructure/mechanical properties引用本文复制引用
出版年
2024
NETL
NSTL
万方数据