Effect of annealing temperature on the microstructure and mechanical properties of an as-rolled Mg--9wt.%Li--3wt.%Al--1wt.%Zn alloy sheet
Meng-Chang LIN1,2,Shang-Qiu LIN1,Jun-Yen UAN1,*()
1. Department of Materials Science and Engineering, Chung Hsing University, 250 kuo-kuang Rd., Taichung 40277, Taiwan, China 2. Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, 195 Sec. 4, Chung-Hsing Road, Hsin-Chu 31040, Taiwan, China
This study investigated the effect of annealing temperature on the mechanical properties of an as-rolled Mg--9.26wt.%Li--3.03wt.%Al--1.10wt.%Zn (LAZ931) alloy sheet. The dual-phase (α+β) LAZ931 alloy plate of 3 mm in thickness were rolled (67% reduction) and then annealed at temperatures at 100°C--350°C. The alloy's ductility showed a sharp concave downward tendency as a function of annealing temperature. The elongation of the LAZ931 alloy sheet increased with annealing temperature up to 150°C, followed by a sharp decrease of the alloy’s ductility as the annealing temperature higher than 150°C. The specimen exhibited an extremely low elongation (only ~0.5%) at annealing temperature around 300°C. Formation of brittle AlLi particles on boundary resulted in Li depletion zone near by grain boundary, transforming the Li depletion zone into α (hcp) layer. The combined effects including brittle AlLi particles on boundary and the hcp α layer on boundary resulted in the brittlement of the high-temperature-annealing sample.
. [J]. Frontiers of Materials Science, 2014, 8(3): 271-280.
Meng-Chang LIN,Shang-Qiu LIN,Jun-Yen UAN. Effect of annealing temperature on the microstructure and mechanical properties of an as-rolled Mg--9wt.%Li--3wt.%Al--1wt.%Zn alloy sheet. Front. Mater. Sci., 2014, 8(3): 271-280.
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