GH3230合金焊接板材长期热暴露后组织和性能研究  

Microstructure and Properties of GH3230 Welded Plates After Long-Term Heat Exposure Treatment

作　　者：张天昊 鞠泉 蒙肇斌 王浩[1] Zhang Tianhao;Ju Quan;Meng Zhaobin;Wang Hao(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing CISRI-Gaona Materials Technology Co.,Ltd,Beijing 100081,China)

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]北京钢研高纳科技股份有限公司,北京100081

出　　处：《稀有金属材料与工程》2023年第7期2573-2581,共9页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51571020)。

摘　　要：研究了GH3230合金焊接板材在经过不同温度(700~1000℃)、不同时间(1000~2000 h)的长期热暴露处理后显微组织和力学性能的变化。结果表明:热暴露处理后熔化区铸态组织的枝晶成分偏析程度显著降低,并且随着热暴露温度的升高,降低效果更明显,逐渐形成晶粒组织。在800℃以上长期热暴露后,室温抗拉强度和屈服强度有所降低,延伸率逐渐上升,主要是由于热影响区小颗粒状(CrW)_(23)C_(6)碳化物回溶和W_(6)C碳化物粗化导致的。随热暴露温度升高,高温持久断裂时间明显降低,而持久塑性有所升高,母材晶粒尺寸较小和碳化物粗化是焊接板材断裂在母材处的原因。The changes of microstructure and mechanical properties of GH3230 alloy welded plate after long-term heat exposure treatment at different temperatures(700-1000 ℃) and different time(1000-2000 h) were studied.The results show that the degree of dendrite segregation of as cast microstructure in the melting zone is significantly reduced after heat exposure treatment,and with the increase in heat exposure temperature,the reduction effect is more obvious,and the grain structure is gradually formed.The tensile strengths and yield strengths at room temperature decrease after heat exposure at temperatures above 800 ℃,and the elongation increases,which is mainly caused by the solubilizing of small granular(CrW)_(23)C_(6) carbides in the heat affected zone and the coarsening of W_(6)C carbides.With the increase in heat exposure temperature,the protracted rupture time significantly decreases,while the endurance plasticity increases.The change of grain size and carbide coarsening are the reasons for fracture of welded plates at the base metal.

关 键 词：GH3230合金 长期热暴露 热影响区 显微组织 力学性能 

分 类 号：TG132.33[一般工业技术—材料科学与工程]