Aging behavior of an in-situ TiB{sub 2}/Al-Cu-Li-x matrix composite

Journal Article · Wed Feb 15 04:00:00 EST 2017 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2016.11.034· OSTI ID:22689703

Shen, Yanwei; Hong, Tianran; Geng, Jiwei; Han, Gaoyang; Chen, Dong; Li, Xianfeng; Wang, Haowei

Transmission electron microscopy, differential scanning calorimetry and hardness tests have been performed on an in-situ TiB{sub 2}/Al-3.3Cu-1.0Li-0.60Mg-0.40Ag-0.14Zr-0.13Si composite to study its aging behavior at 175 °C. A cubic phase suspected to be the σ (Al{sub 5}Cu{sub 6}Mg{sub 2}) phase or its variant is precipitated at all aging stages studied, and this phase is not typically observed in the Al-Cu-Li alloys. The primary hardening (aging for 3 h) phases consist of δ′ (Al{sub 3}Li), β′ (Al{sub 3}Zr) and the cubic phase. After aging for 18 h, all precipitates including T{sub 1} (Al{sub 2}CuLi), S (Al{sub 2}CuMg), θ′ (Al{sub 2}Cu), δ′, β′ and the cubic phase have appeared, and the formation of T{sub 1} and S results in a rapid increase in hardness. With prolonging of aging time, the apparent coarsening of T{sub 1} and S results in a decline in hardness. - Highlights: •The aging behavior of an in-situ TiB{sub 2}/Al-Cu-Li-x composite was studied. •A cubic phase suspected to be σ (Al{sub 5}Cu{sub 6}Mg{sub 2}) or its variant was precipitated. •The hardness change was dominated by the evolution of T{sub 1} (Al{sub 2}CuLi) and S (Al{sub 2}CuMg).

• OSTI ID: 22689703
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 124; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGING
ALUMINIUM ALLOYS
CALORIMETRY
COPPER ALLOYS
HARDENING
HARDNESS
LITHIUM ALLOYS
PRECIPITATION
TITANIUM BORIDES
TRANSMISSION ELECTRON MICROSCOPY