抄録
Age hardening characteristics of Mg-Al-Mn system alloys cast in to iron mold were investigated by means of hardness measurement and microstructure observation with optical microscopy. As for the age hardening behavior of the Mg-Al-Mn system alloys, peak-age hardness was increased with increasing the aluminum content in all aging temperature, and the peak-age time was shifted to the side for a short time remarkable. Pre-precipitation area was not observed in AM60 magnesium alloy iron mold castings in the condition of over-aged contrastively in AM60 magnesium alloy sand mold castings. Age hardening behavior of Mg-Al-Mn system iron mold castings depended on the cellular precipitation with increasing the aluminum content and aging temperature, as a result of hardness measurement in cellular and intragranular precipitation phases for AM60, AM80 and AM90 magnesium alloys.
