A Study on the Hot Deformation Behaviors of Al - Li alloys
진영철Y . C . Jin, 류창영C . Y . Yoo
Abstract
Tensile properties at room and high(100, 200 and 300℃) temperatures were studied for the Al-2.0 wt%Li binary alloy and Al-2.0wt.%Li ternary alloys with the addition of either 1.2 wt%Cu, 1.0 wt%Mg or 0.12 wt%Zr. The tensile and yield strengths of Al-2.0 wt%Li alloy were decreased rapidly with increasing the test temperature above 100℃. The tensile strength at 300℃ of this alloy is less than 6 Kg/㎟. This rapid decrease in strength results from coarsening of δ` phase and precipitation of stable δ phase. The strength of the Al-2.0 wt%Li-1.2wt%Cu alloy were much higher than that of the binary alloy because of the solution and precipitation hardening. The strengths of Al-2.0wt%Li-1.0wt%Mg alloy were higher than those of the binary alloy due to the solid solution hardening and the homogeneous distribution of δ` phase, but lower than those of the Cu-added ternary alloy. The strength of the Al-2.0wt%Li-0.12wt%Zr alloy was slightly higher than those of the binary alloy due to the grain refinement and the precipitation of a composite phase.