Al-1.3 wt%Mg<SUB>2</SUB>Si合金のGPゾーンと中間相の析出におよぼすSn添加の効果

Abstract

The effects of additional element Sn on GP zone formation and transition phase precipitation were investigated by measurments of the change of the age-hardening and electron micrograph observations. The results obtained were summarized as follows:(1) The behavior of aging at a temperature below 190°C was delayed by the effect of additional element Sn. This effect became more remarkable with decreasing temperature.(2) At aging temperatures above 230°C, the rate of age-hardening was increased and the size of the precipitate became smaller by the addition of Sn.(3) The critical temperature of the aging behavior was decreased and the reaction order of the precipitation was increased at a temperatures below the critical temperature by the effect of additional element Sn.The above results can be explained by the facts that GP zone formation is delayed and the frequency of the nucreation of transition phase is increased by the effect of additional element Sn.