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研究了预拉伸量和时效温度对ＣＰ２７６ 铝锂合金组织与性能的影响。结果表明， 时效前的预拉伸可促进Ｔ１ 相异质形核， 显著提高合金的沉淀强化效果， 但同时指出， 过大的预拉伸量（ ＞ ６ ％ ） 导致位错胞状缠结， 降低 Ｔ１ 相分布的均匀性， 对合金性能不利。时效温度则对晶界ＰＦＺ 影响显著， 高温时效的合金ＰＦＺ 较宽， 强度与塑性很差。该合金的最佳应变时效制度为：３ ％ ～６ ％ 预拉伸＋ １６０ ℃时效１６ ～２０ ｈ ，该制度下合金具有较好的综合力学性能（σｂ ＝ ５６３ ＭＰａ ， σ０ ．２ ＝ ５２１ ＭＰａ ， δ＝ ６ ．６ ％ ） 。
The effects of pre-stretch and aging temperature on microstructure and properties of CP276 Al-Li alloy were investigated. The results show that the pre-stretch before aging can promote the heterogeneous nucleation of T1 phase and significantly improve the precipitation strengthening effect of the alloy. However, it is pointed out that excessive pre-stretching (> 6%) leads to dislocation cell-like entanglement and decreases The uniformity of the T1 phase distribution adversely affects the properties of the alloy. The aging temperature has a significant impact on the grain boundary PFZ, high temperature aging alloy PFZ wide, poor strength and ductility. The optimum strain-aging regime of the alloy is as follows: pre-tension of 3% -6% and aging time of 16-20 h at 160 ℃. The alloy has better mechanical properties (σb = 563 MPa, σ0.2 = 521 MPa , Δ = 6.6%).