Effect of one-step and two-step homogenization treatments on distribution of Al3Zr dispersoids in commercial AA7150 aluminium alloy

doi:10.1016/S1003-6326(11)61512-4

Transactions of Nonferrous Metals Society of China

Volume 22, Issue 11, November 2012, Pages 2645-2651

https://doi.org/10.1016/S1003-6326(11)61512-4 Get rights and content

Abstract

Semi-quantitative electron probe microanalysis (EPMA) mapping, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to study the effect of one-step and two-step treatments on the Zr distribution and Al₃Zr dispersoid characteristics in as-cast commercial AA7150 aluminum alloy. It is shown that the Zr concentration in the dendrite centre regions is higher than that near the dendrite edges in the as-cast condition, and that homogenization at 460 °C for 20 h is insufficient to remove these concentration gradients. After homogenizing at 460–480 °C, a high number density of larger dispersoids can be observed in dendrite centre regions but not near dendrite edges. Furthermore, the dispersoid size increases with increasing the temperature during both one-step and two-step homogenization treatments.

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Citation Excerpt :
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Effect of one-step and two-step homogenization treatments on distribution of Al3Zr dispersoids in commercial AA7150 aluminium alloy

Abstract

Materials Science and Engineering A

Materials Characterization

Acta Materialia

Materials Science and Engineering A

Materials Science and Engineering A

Acta Materialia

Ultramicroscopy

Acta Materialia

Effect of one-step and two-step homogenization treatments on distribution of Al₃Zr dispersoids in commercial AA7150 aluminium alloy