Hot isostatic pressing synthesis and mechanical properties of Al/Al-Cu-Fe composite materials

Metal-matrix composites are produced from Al powder and 30 vol% of icosahedral Al-Cu-Fe quasi - crystalline particles using a hot isostatic pressing technique. It is demonstrated that the initial icosahedral phase is transformed into the omega-Al70Cu20Fe10 tetragonal phase during the hot isostatic pressing (HIP) process. The mechanical properties of the composite were evaluated over the temperature range 293 to 773 K by performing compression tests at constant strain rate. The temperature dependence of the yield stress gives evidence of two temperature regimes with a transition temperature at approximately 423 K. Strain-rate sensitivity measurements support the change in rate-controlling deformation mechanisms at this temperature. It is proposed that cross-slip and/or climb mechanism control plastic flow. Finally, it is suggested that the phase transformation of the particle contributes positively to the improvement of the mechanical properties.