Temperature Dependence of Hardness and Expansion in an Icosahedral Al-Pd-Mn Alloy

Abstract
Temperature dependence of hardness and expansion in icosahedral Al72Pd20Mn8 alloy (i-AlPdMn) are examined in comparison with a cubic Al60Pd25Mn15 alloy (c-AlPdMn). The hardness at room temperature is about 780 kg/mm2 for i-AlPdMn, much greater than that for c-AlPdMn of 420 kg/mm2, and decreases to about 200 kg/mm2 at 973 K. The thermal expansion of i-AlPdMn is found to be linear versus temperature and the thermal expansion coefficient is estimated to be ~14.6×10-6 K-1.