Abstract:
Aluminum-based composites reinforced with
in-situ Al
2O
3, TiB
2 and Al
3Ti particles were prepared through reactive hot pressing from Al, B
2O
3 and TiO
2 powders and Al, B and TiO
2 powders. There is fine Al
3Ti precipitation in composite fabricated by Al, B, TiO
2 powders. The low cycle fatigue behavior of
in-situ composites was investigated under total strain-controlled conditions at the room temperature. The composite free of precipitation Al
3Ti phase exhibits a stable cyclic response at lower total strain amplitudes. The cyclic hardening in the first cycle followed by cyclic softening occurs in the composite free of precipitation at higher total strain amplitudes.The composite containing Al
3Ti phase exhibits a stable cyclic response at all amplitudes adopted in the study. The sets of crack initiation are broken Al
3Ti phase, the debonded interface between Al
3Ti phase and matrix, and microcracks in the matrix. The cracks propagate through the matrix, passing by Al
2O
3 and TiB
2 particles. The fatigue life of two composites can be described by the Coffin-Manson relationship.