摘要
针对650℃超超临界火电机组使用的新型铁镍基高温合金材料,通过微观组织观察,开展了高温时效过程中的组织演化规律研究。结果表明,在650℃时效时,合金中晶界和晶内无明显析出相析出。随着时效温度提高和时间延长,晶界以颗粒状的TiC和M_(23)C_(6)碳化物析出相为主,呈链状分布;晶内以球状γ′强化相为主,尺寸由几纳米增加到几十纳米。此外,在800℃及850℃时效时,合金中部分区域出现晶界迁移现象,形成了析出相贫化与不连续粗化区。
The evolution laws of microstructure in a novel Fe-Ni based superalloy utilized in ultra-supercritical thermal power generating units during high temperature aging treatment were investigated through methods such as microstructure observation.The results show that aging at 650℃,there is no obvious precipitate in the grain boundary and in the crystal.With the increase of aging temperature and time,granular TiC and M 23 C 6 carbide precipitates are mainly distributed in chain pattern at grain boundaries.The sphericalγ'reinforced phase is mainly distributed in the crystal,and the size increases from a few nanometers to tens of nanometers.Furthermore,some grain boundaries migrated at the aging temperature of 800℃and 850℃,forming precipitation dilution zones and discontinuous coarsening zones.
作者
李生志
孙林根
霍鑫
丁丽锋
刘霞
沈红卫
程俊
杨振刚
刘瞿
LI Shengzhi;SUN Lingen;HUO Xin;DING Lifeng;LIU Xia;SHEN Hongwei;CHENG Jun;YANG Zhengang;LIU Qu
出处
《大型铸锻件》
2024年第6期65-68,93,共5页
Heavy Casting and Forging
基金
国家重点研发计划项目(2023YFB4102300650℃及以上高参数高效燃煤发电技术及示范)。
关键词
铁镍基合金
高温时效
组织演化
晶界迁移
Fe-Ni based superalloy
high temperature aging treatment
microstructural evolution
grain boundary migration
