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Ａｌ－０．６Ｍｇ－０．８Ｓｉ－０．２Ｃｒ合金中加入不同含量的Ｌｉ后，无针状Ｍｇ２Ｓｉ相析出，而形成近球形ＡｌＬｉＳｉ相，δ′成为主要时效析出相。Ｌｉ的加入量为１．７％时，δ′相体积分数和晶界析出相的线密度低，其时效硬化过程缓慢，峰值强度显著降低，但具有较好的延伸率；Ｌｉ的加入量为２．６时，δ′相体积分数高，其时效硬化速度与基体合金相近，但具有更高的峰值强度，大量δ′相的存在产生强烈的共面滑移倾向，合金的延伸率略有下降。
Al-0.6Mg-0.8Si-0.2Cr alloy by adding different Li content, the needle-free Mg2Si phase precipitation, and the formation of nearly spherical AlLiSi phase, δ ’become the main aging precipitation phase. When the addition amount of Li is 1.7%, the volume fraction of δ ’phase and the linear density of precipitation phase at the grain boundary are low, the aging hardening process is slow, the peak intensity is significantly reduced, but with good elongation; the addition amount of Li is 2.6, the phase fraction of δ ’phase is high, its age hardening rate is similar to that of the matrix alloy, but it has higher peak intensity. The presence of a large amount of δ’ phase has a strong tendency of coplanar slip, and the elongation of the alloy is slightly decline.