预拉伸对5182-O和5754-O铝合金屈服平台的影响

Influence of pre-stretching on yield platform of 5182-O and 5754-O aluminum alloys

O状态的高Mg含量铝合金室温变形时材料表面容易出现吕德斯带。为了深入了解其机制,试验研究了不同预拉伸变形量对5182-O和5754-O铝合金板屈服平台的影响,并且对预拉伸试样进行了TEM分析。试验结果表明:随着预拉伸量的增加屈服平台长度减少,预变形量达到1.0%时屈服平台消失,同时屈服平台的长度与合金成分有关。TEM分析表明位错密度对5182-O和5754-O铝合金的屈服平台的形成起关键作用。

It is easy to form Lüders band on the surface of Al alloy in O temper with high Mg content at room temperature.In order to further understand the mechanism,the effect of different pre-stretching deformation on the yield platform of 5182-O and 5754-O aluminum alloy plates was experimentally studied,and the pre-stretching samples were analyzed by TEM.The experiment result shows that the length of yield platform decreases with the increase of pre-stretching amount.The yield platform disappears when the pre-deformation reaches 1.0%,and the yield platform length is related to the alloy composition.TEM analysis shows that dislocation density plays a key role in the formation of yield platform of 5182-O and 5754-O aluminum alloys.