摘要
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。
The effect of Li content on the precipitation behavior and mechanical properties of AlMgSi alloy has been investigated. In AlLiMgSi alloy, the ordered δ′ phase became the predominant precipitate and no GP zones of Mg2Si are observed at peak aging condition. The 1.6%Li containing alloy shows slow aging reactions , limited hardening response and weak coplanar slip tendency, due to the small volume fraction of δ′ phase. While the 2.6% addition produces a strong aging response, a higher σb at peak aging condition and extensive coplanar slip tendency under tensile stress, due to the formation of large amounts of homogeneously distributed δ′ phase.
出处
《航空材料学报》
EI
CAS
CSCD
1998年第2期8-13,共6页
Journal of Aeronautical Materials
基金
航空科学基金
关键词
时效硬化
力学性能
显微组织
铝锂合金
AlLiMgSi alloys,aging precipitation,mechanical properties,microstructures