Aluminum matrix composites can exhibit exceptionally high compressive
strength (greater than or equal to 4 GPa). The main failure mechanism
has been identified to be plastic kinking, although an upper bound see
ms to be attained when the fibers reach their compressive strength. Th
e experimental results are consistent with a plastic kinking model in
strain hardening composites. The important parameters controlling the
compressive strength are the composite shear modulus, the shear yield
strength, the strain hardening rate and the maximum initial fiber miso
rientation. Interfaces can also play an important role; composites rei
nforced with weakly bonded fibers have a reduced compressive strength
due to their low shear strength in the fiber direction. The results ca
n be used to design composite systems with high compressive strengths;
in practice this is done by selecting matrices with high yield streng
ths and fast hardening rates. (C) 1997 Acta Metallurgica Inc.