摘要
目的揭示奥氏体晶粒粗化对该钢管服役可靠性的影响。方法采用预变形加固溶处理工艺制备粗晶试样,以模拟长期高温服役TP347HFG钢管中奥氏体晶粒异常长大状态。开展650℃直至3600 h时效后的粗、细晶TP347HFG钢试样显微组织及力学性能的对比研究。结果高温时效过程中,粗、细晶试样奥氏体晶粒大小基本保持不变,孪晶密度降低。第二相颗粒析出行为没有明显差异,M_(23)C_(6)相颗粒优先在奥氏体晶界析出、粗化,但粗晶试样中的M_(23)C_(6)相析出更快,粗化更明显。随时效时间延长,粗、细晶试样的室温、高温拉伸力学性能变化趋势基本一致,室温、高温强度变化不明显,但塑性相差较大。经650℃时效3600 h后,粗晶试样600℃拉伸时的断后伸长率较细晶试样显著下降了30.4%。结论粗晶TP347HFG钢管的高温塑性应受到重点关注。
The work aims to reveal the effect of austenite grain coarsening on the service reliability ofsteel tubes.Coarse-grainedspecimens were prepared via a pre-deformation and solid solution treatment method to simulate the abnormal growth state of the austenite grains of the TP347HFG steel tubes in long-term service.Microstructures and mechanical properties of the coarse-/fine-grained TP347HFG steel specimens aged at 650℃for 3600 h were comparatively studied.During high-temperature aging,the austenite grain sizes of the coarse-/fine-grained specimenswere almost unchanged,but the twin densities decreased.Secondary phase precipitation was not apparently different.The M_(23)C_(6)phase particles preferentially precipitated and coarsened at the austenite grain boundaries,which was more severefor the M_(23)C_(6)phase particles in the coarse-grained specimens.As the aging time prolonged,the variation tendencies of the room-/high-temperature tensile strengths and plasticity of the coarse-/fine-grainedspecimenswere basically consistent.The strengths at room temperature and high temperature did not obviously change,but the plasticity was greatly distinct.After aging at 650℃for 3600 h,the elongation after fracture at 600℃of the coarse-grained specimendecreased by 30.4%than that of the fine-grained one.More attention should be paid to the high-temperature plasticity of the coarse-grained TP347HFG steel tube.
作者
程翔
鲍峥
王若民
缪春辉
陈国宏
汤文明
CHENG Xiang;BAO Zheng;WANG Ruomin;MIAO Chunhui;CHEN Guohong;TANG Wenming(Anhui Xinli Electric Technology Consulting Co.,Ltd.,Hefei 230601,China;School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China;Electric Power Research Institute,Anhui Electric Power Co.Ltd.,State Grid,Hefei 230601,China)
出处
《装备环境工程》
CAS
2024年第10期143-150,共8页
Equipment Environmental Engineering
基金
安徽新力电业科技咨询有限责任公司科技项目(2022咨-KJ-02)。
作者简介
通信作者:汤文明。
