SHOCK CONSOLIDATION OF ALUMINUM-LITHIUM POWDER.

Shock consolidation experiments on approximately 50 mu m diameter Al-3% Li and Al-1. 1% Li rapidly solidified process (RSP) single phase alloy powder were conducted in the 1. 6 to 4. 8 GPa range. A limited number of experiments were conducted also on RSP 2024 Al powder. The samples an initial density 60% of the crystal density, and were impacted with gun and explosive launched Al and Fe flyer plates at 0. 8 to 1. 3 km/sec. Consolidation to a theoretical density of 2. 46 and 2. 74 mg/m**3 was achieved for the Al-3% Li and Al-1. 1% Li, respectively. The data permit calculations of parameters (shock pressure and energy) for shock consolidation map theory. Extensive interparticle bonding is achieved upon shock consolidation. TEM observations suggest that cracks in the consolidated material occur due to failure of interparticle phase which are Mg-rich. Preannealing at 400 to 550 degree C (in addition to dehydroxylation at 277 degree C of the LiOH and Al (OH)//3 on the surface of the RSP powder) decreases the macroscopic crack density and increases the quality of interparticle bonds. Tensile tests of explosively consolidated Al-3% Li resulted in a (0. 2% strain) yield strength of 16 minus 19 multiplied by 10**3 psi. Ductile failure was observed after a small elongation (0. 7%).