Cu含量对Al—Mg—Si合金析出及烤漆硬化行为的影响

采用DSC、硬度测试及TEM研究A16016铝合金中Cu含量对淬火及淬火预时效样品的人工时效析出和硬化行为的影响。结果表明，微量Cu有利于形成较大且稳定性较好的GPI，能在随后的人工时效过程中进一步向GPII转化，从而提高合金的烤漆硬化能力。但是，当Cu含量为0．3％时，烤漆硬化能力没有得到显著增加。对于含Cu合金，预时效热处理也能有效地抑制合金的自然时效行为。

Effect of copper on precipitation and baking hardening behavior of Al-Mg-Si alloys

The effects of copper on the ageing precipitation behavior of as-quenched and pre-aged AA6016 aluminum alloy were studied by differential scanning calorimetry （DSC）, Vickers hardness measurement and transmission electronic microscopy （TEM）. The results indicate that the addition of copper facilitates the growth of clusters （GP I） to the critical size during pre-ageing. Therefore, the addition of copper accelerates the transition from GP I （pre-β＂） to GP II （β＂） during final artificial ageing, and finally results in the favorable paint-bake response. However, the one with the copper level of 0.3% does not show significant baking hardening response as expected. Pre-aging can also reduce the detrimental effect due to natural aging of copper-containing alloys.