Fabrications and mechanical properties of bulk amorphous, nanocrystalline, nanoquasicrystalline alloys in aluminum-based system

By controlling the composition, clustered atomic configuration and stability of supercooled liquid by the rapid solidification and powder metallurgy techniques, high-strength Al-based bulk alloys containing nanoscale nonperiodic phases were produced in Al–Ln–LTM, Al–ETM–LTM and Al–(V, Cr, Mn)–LTM (Ln=lanthanide metal, LTM=VII and VIII group transition metals, ETM=IV–VI group transition metals) alloys containing high Al contents of 92–95 at.%. The nonperiodic phases are composed of an amorphous or an icosahedral quasicrystalline phase. In particular, the Al-based bulk alloys consisting of nanoscale icosahedral particles surrounded by fcc-Al phase exhibit much better mechanical properties exceeding largely those for the commercial high-strength type Al-based alloys. The success of producing the Al-based alloys with good engineering properties by use of the icosahedral phase is promising for future development of icosahedral base alloy as practical materials.