本文關(guān)鍵詞： 單晶鎳基合金 Re TCP相 元素偏析 蠕變　出處：《中國(guó)有色金屬學(xué)報(bào)》2015年06期 　論文類型：期刊論文

【摘要】：通過(guò)對(duì)一種4.5%Re(質(zhì)量分?jǐn)?shù))鎳基單晶合金進(jìn)行不同工藝熱處理、蠕變性能測(cè)試及組織形貌觀察,研究了固溶時(shí)間對(duì)該合金組織結(jié)構(gòu)與高溫蠕變行為的影響。結(jié)果表明:鑄態(tài)合金中各元素存在較大的成分偏析,經(jīng)高溫長(zhǎng)時(shí)間固溶及時(shí)效處理后,合金中各元素在枝晶間/臂的偏析程度明顯降低;將固溶時(shí)間由10 h延長(zhǎng)至24 h后,合金在1100℃、137 MPa的蠕變壽命由101 h提高至164 h;其中,10 h固溶處理合金中仍存在較大程度的元素偏析,并且在蠕變期間,析出針狀TCP相。合金在高溫蠕變期間的變形機(jī)制是位錯(cuò)在基體中滑移和剪切筏狀γ′相;蠕變后期,大量位錯(cuò)剪切筏狀γ′相,致使近斷口區(qū)域的筏狀γ′相扭曲,在筏狀γ/γ′兩相界面發(fā)生裂紋的萌生,并沿垂直于應(yīng)力軸方向擴(kuò)展,直至發(fā)生蠕變斷裂。這是合金的高溫蠕變斷裂機(jī)制。
[Abstract]:The creep properties and microstructure of a 4.5 Re-based nickel base single crystal alloy were investigated by heat treatment in different processes. The effect of solution time on the microstructure and creep behavior of the as-cast alloy was studied. The segregation degree of each element in the interdendrite / arm was obviously decreased, and the solution time was prolonged from 10 h to 24 h. The creep life of the alloy was increased from 101h to 164h at 1 100 鈩，

本文編號(hào)：1553865