A high strength Al-Li alloy produced by laser powder bed fusion: Densification, microstructure, and mechanical properties

High strength 2195 Al-Li alloy samples produced by laser powder bed fusion (LPBF) were obtained in this study. The microstructure and mechanical properties were investigated for both the as-fabricated and T6 heat-treated samples. The as-fabricated sample showed a coarse columnar grain microstructure, heterogeneous element distribution, high density of dislocations, and complex precipitation types. After T6 heat treatment, the dominate strengthening T-1 (Al2CuLi) plates precipitated in the matrix, and the dislocation density remained high. The asfabricated 2195 sample showed a yield strength (YS) of 207.7 +/- 1.5 MPa, an ultimate tensile strength (UTS) of 340.7 +/- 2.9 MPa, and elongation of 17.2 +/- 0.9%. After T6 heat treatment, the YS and UTS were dramatically increased to 521.3 +/- 14.4 MPa and 587.0 +/- 7.2 MPa, and the elongation was 6.9 +/- 0.3%. The LPBF of the high strength Al-Li alloy was successfully confirmed.