Microstructure and Mechanical Properties of Al-Cu-Cr Quasicrystals/Al Matrix Composites Synthesized by Hot-Pressing Technique

Abstract

Microstructure and mechanical properties of 20% Al-Cu-Cr/Al composites synthesized by hot-pressing technique after annealing, quenching and aging was studied by means of X-ray diffractometer (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and uniaxial compressive test. Microstructure of Al-Cu-Cr particles in the composites after hot-pressing is mainly consist of icosahedral quasicrystals and which transformed into decagonal quasicrystals after annealing. Microstructure of matrix in the composites after hot-pressing, annealing, quenching and aging is pure Al, Al + Al2Cu, supersaturated solid solution Al and Al + Al-Cu transition phases respectively. Hardness, fracture strength and the Young’s modulus of the composites are improved by age-hardening.