热处理冷却速度对IN792合金显微组织及持久性能的影响  

Effect of cooling rate in heat treatment on microstructure and stress-rupture properties of IN792 alloy

作　　者：胡聘聘[1] 盖其东[1] 李相辉[1] 陈晶阳[1] 汤鑫[1] 

机构地区：[1]北京航空材料研究院先进高温结构材料重点实验室,北京100095

出　　处：《金属热处理》2017年第2期124-130,共7页Heat Treatment of Metals

摘　　要：研究了热处理冷却速度对IN792合金显微组织及760℃/662 MPa持久性能的影响。结果表明,热处理冷却速度对γ'相的析出有显著影响:与炉冷相比,空冷和油冷条件下较快的冷却速度细化了合金二次γ'相尺寸,同时促进三次γ'相的析出,获得了尺寸、形貌不同的两种γ'相相匹配的双态组织。这种组织特点使合金760℃/662 MPa的持久寿命由炉冷条件下的118 h提高到空冷条件下的216 h和油冷条件下的245 h,使伸长率由炉冷条件下的8.5%下降到空冷条件下的4.0%和油冷条件下的3.3%。合金经1185℃×2 h,AC+1121℃×2 h,AC+843℃×24 h,AC时效处理,可获得较好的综合性能。Effects of cooling rate in heat treatment on microstructure and stress-rupture properties at 760 ℃ /662 MPa of IN792 alloy were investigated. The results show that the precipitation of γ＇ phase is affected by cooling rate obviously. Compared with furnace cooling in heat treatment,oil cooling and air cooling lead to more fast cooling rate,as a result,the size of secondary γ＇ phases is decreased and the formation of third γ＇ phase is promoted,thus,binary dispersedly distributed γ＇ precipitates with different sizes and morphologies of the tested alloy are achieved. Moreover stress-rupture life at 760 ℃ /662 MPa is improved from 118 h by furnace cooling to 245 h by oil cooling and 216 h by air cooling,and the elongation is decreased from 8. 5% by furnace cooling to 3. 3% by oil cooling and 4. 0% by air cooling. Preferable combination of strength and toughness can be achieved after solution at 1185 ℃ for 2 h,cooling by air,and then aged at 1121 ℃ for 2 h,cooling by air,followed by low temperature aging at 843 ℃ for 24 h,cooling by air.

关 键 词：IN792合金 热处理 冷却速度 显微组织 力学性能 

分 类 号：TG132.32[一般工业技术—材料科学与工程]