北京科技大学学报Issue(6)：763-769,7.
亚固溶温度热处理对 GH720Li 难变形高温合金γ相的影响
Influence of heat treatments at temperatures below the γ solvus onγ phase in nickel-base superalloy GH720Li
摘要
Abstract
The microstructural evolution of γ phase was investigated in difficult-to-deform nickel-base superalloy GH720Li subjected to subsolvus solution heat treatment, 650 ℃ for 24 h → air cooling or 650 ℃ for 24 h → air cooling+ 760 ℃ for 16 h → air cooling after subsolvus solution treatment, and long time aging at 870 ℃ for 3000 h. It is found that the primary γ phase is affected most significantly by subsolvus solution treatment, the degree of partial dissolution increases with increasing solution temperature, and aging treatment makes the primary γ phase turn to sphere or near sphere. However, the secondary and the tertiary γ phase fully dissolve into the matrix during subsolvus solution treatment, re-precipitation during the aging is obvious, and the amount and zone increase with increasing solution temperature. When long time aging at 870 ℃ the microstructure uniformity gradually improves, and the secondary and tertiary γ phase dissolve. The primary γ phase at grain boundaries coarsens a little after 500 h. Besides, the hardness decreases with the aging time prolonging at 870 ℃ before keeping unchanged.关键词
高温合金/镍合金/热处理/相转变/时效Key words
superalloys/nickel alloys/heat treatment/phase transitions/aging分类
矿业与冶金引用本文复制引用
于秋颖,张麦仓,董建新..亚固溶温度热处理对 GH720Li 难变形高温合金γ相的影响[J].北京科技大学学报,2013,(6):763-769,7.基金项目
航空科学基金资助项目(2010ZF74004) （2010ZF74004）
