Effect of Sn on as-cast ageing behavior of Al-Si-Mg alloy

来源期刊：中国有色金属学报(英文版)2003年第3期

论文作者：王桂青 边秀房 段佑峰 张均艳

文章页码：626 - 631

Key words：aluminum alloy; as-cast ageing; precipitates; nucleation density

Abstract: The effect of minor additions of Sn on the as-cast ageing behavior of Al-11Si-0.35Mg alloy was investigated. It is shown that precipitation has been retarded in Sn containing alloy and more time is needed to reach its peak hardness，which is bigger than that of the base alloy. Analysis of the kinetic data shows that Sn addition does not change the growth dependent parameter n, but increases the nucleation density dependent parameter k. TEM results show that there are little precipitates in Sn containing alloy at the initial stage of as-cast ageing. However, the Sn addition increases the net density of precipitates during as-cast ageing, because there are many dislocation loops formed as ageing progresses and Sn segregated at the edges of dislocation loops, which acts as the nuclei of precipitates.