Interaction Between Natural Aging and Pre-Aging Processes and its Impact on the Age-Hardening Behavior of Al-Mg-Si Automotive Sheets
- 79 Downloads
Pre-aging (PA) treatment, employed shortly or for a long time after solution treatment, has different effects on the age-hardening of Al-Mg-Si automotive sheets. Here, the influence of natural aging and PA on the age-hardening behavior was systematically investigated. The aging response decreased with increasing room temperature (RT) storage time and RT storage time before PA treatment. The clustering activity before paint bake-hardening (BH) had little effect on the average r values of the alloy sheets. The hardness of the NA0 sample (No RT + No PA) was higher than that of NA0PA sample (No RT + PA) during paint BH at 185°C. The difference in hardness decreased significantly with increasing RT storage time. The cluster type formed before paint BH significantly affected the size and distribution of the strengthening precipitates, resulting in a variation in peak aged hardness.
The authors acknowledge financial support from the Project 51790485 supported by National Natural Science Foundation of China and thank LetPub (www.letpub.com) for its linguistic assistance during the preparation of this manuscript.