含Sc铝镁合金超塑变形行为与显微组织特征

来源期刊：中南大学学报(自然科学版)1999年第2期

论文作者：潘青林 尹志民 杨磊 左铁镛

文章页码：69 - 71

关键词：钪;铝合金;超塑变形;显微组织;动态再结晶

Key words：scandium; aluminium alloy; superplastic deformation; microstructure; dynamic recrystallization

摘    要：研究了含微量Sc元素的Al-Mg合金在超塑变形过程中的力学行为和显微组织．结果表明：合金可在较宽温度和应变速率范围内获得良好的超塑性．在温度为520℃，初始应变速率为 1.67×10^－３ｓ^－１条件下拉伸变形时最大延伸率可以达到396%．显微组织分析发现，合金的超塑性效应是由变形初期的动态再结晶诱发产生，其超塑变形过程可分为亚晶超塑性阶段、过渡阶段和细晶超塑性阶段．

Abstract: The change of mechanical behavior and microstructure of Al-4.43Mg-0.41Sc alloy during superplastic deformation has been studied. The results show that the alloy exhibits excellent superplasticity in a wide range of temperature and initial strain rate. Its maximum elongation may be up to 396% under tensile deformation with initial strain rate 1.67×10^-3 s^-1 at temperature 520 ℃. The TEM observation of the microstructure changes revealed that the superplasticity obtained was induced by the dynamic recrystallization which occurred in the early stage of deformation. The whole deformation process can be divided into three stages of subgrain superplasticity, transition and fine grain superplasticity.