摘要
采用高温热处理炉对超超临界电站锅炉用HR3C合金进行短时时效和650℃×500h时效,研究了时效对合金微观组织和冲击韧度的影响。结果表明,短时时效后,晶内存在少量一次大块NbCrN相,同时有少量细小的Z相析出。在650℃×500h时效后,晶内析出更多细小的Z相,经短时时效,合金晶内的Z相更多,其弥散强化提高了合金的显微硬度;晶界析出M23C6相并进一步粗化长大,晶界附近有弥散块状的M_(23)C_6相析出。长期时效后,固溶态和短时时效态合金的冲击韧度降低,断口沿晶断裂。
HR3C alloy was treated with aging treatment and long-term aging at 650 ℃ for 500 h to ana- lyze influence of aging treatment on the microstructure and impact toughness. The results reveal that a few large bulky NbCrN phase an be observed with precipitation of a little tiny Z-phase particles at inner- grain after aging treatment. More Z-phase is precipiated in alloy with aging treatment after long-term aging at 650 ℃ for 500 h, which improves the microhardness by dispersedly strengthening effects. Meanwhile, M23C6 type carbides are coarsened along the grain boundaries, while some M23 C6 particles are distributed randomly inside the austenitic grain. The impact toughness values of HR3C alloy with solid solution treatment or aging treatment are decreased after long-term aging, and the fracture mor- phologies of the notched impact specimens are characterized by intergranular fracture mode.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2017年第7期711-715,共5页
Special Casting & Nonferrous Alloys
基金
西安热工研究院有限公司科技项目(ZD-15-TYK07)
华能国际股份有限公司科技项目(ZD-15-HJK02)
