(西北工業(yè)大學(xué) 機(jī)電學(xué)院， 西安 710072)
摘 要: 采用TEM觀察2090和2090＋Ce兩種鋁鋰合金中δ′相和T1相與位錯(cuò)的交互作用行為， 利用圖形定量分析結(jié)果和微觀變形理論分別計(jì)算兩個(gè)相的強(qiáng)化貢獻(xiàn)， 進(jìn)而分析兩相復(fù)合強(qiáng)化作用形式。 分析結(jié)果表明： 在近峰值時(shí)效區(qū)域， δ′和T1相強(qiáng)化作用的疊加關(guān)系與q=1.4的關(guān)系符合較好； 欠時(shí)效時(shí)， δ′、 T1相強(qiáng)化貢獻(xiàn)的疊加關(guān)系接近線性關(guān)系(q=1)； 過(guò)時(shí)效時(shí)， 卻與拋物線型關(guān)系(q=2)符合較好。 δ′和T1相強(qiáng)化作用的疊加關(guān)系對(duì)時(shí)效時(shí)間表現(xiàn)出較強(qiáng)的依賴性。
關(guān)鍵字: 鋁鋰合金; 沉淀相; 強(qiáng)化
（ School of Mechatronic Engineering, Northwestern Polytechnical University,
Xi'an 710072, China）
Abstract: The microstructures of dislocation in two kinds of aluminum-lithium alloy 2090 and 2090+Ce were observed by TEM. The contribution of precipitates of δ′ and T1 phases were separately calculated by the results of quantitative metallography and micro-deformation theory. Furthermore, the co-strengthening effects of δ′ and T1 phases were studied. The results show that the adding relationship of co-strengthening of δ′ and T1 phases accords with that of q=1.4 at near peak-aged condition. But the adding relationship is approximately linear relation (q=1) at under-aged condition, and become parabola form at over-aged (q=2). The adding relation of co-strengthening contribution of δ′ and T1 phases is obviously dependent on aging time.
Key words: aluminum-lithium alloy; precipitates phase; strengthening
