Effects of two-step homogenization on precipitation behavior of Al3Zr dispersoids and recrystallization resistance in 7150 aluminum alloy
Effects of two-step homogenization on precipitation behavior of Al3Zr dispersoids and recrystallization resistance in 7150 aluminum alloy
复制标题
DOI：
10.1016/j.matchar.2015.02.016
复制
发表时间：
2015-04-01
影响因子：
4.7
通讯作者：
Chen, X. -Grant
中科院分区：
文献类型：
--
作者：
Guo, Zhanying;Zhao, Gang;Chen, X. -Grant
采用透射电镜（TEM）研究了两步均匀化处理对7150合金中Al 3 Zr弥散相析出行为的影响。在均质化期间应用两步处理，其中第一步在300-400 ° C的温度范围内，随后第二步在470 ° C下。与传统的一步均匀化处理相比，两步均匀化处理可获得更细的Al 3 Zr弥散相颗粒尺寸和更高的数密度。使用保持在300 ℃的第一步骤获得最有效的分散质分布。此外，两步均匀化最小化了无沉淀区，并大大增加了枝晶晶界附近弥散相的数量密度。利用电子背散射衍射（EBSD）技术定量分析了两步均匀化处理对不同Zr含量的7150合金再结晶抗力的影响。结果表明，对于含0.04- 0.09wt.%的7150合金，两步热处理改善了弥散相的分布，有效地抑制了变形后退火的再结晶过程Zr的加入使再结晶晶粒的体积分数和晶粒尺寸显著减小。(C)2015 Elsevier Inc. All rights reserved.
The effect of two-step homogenization treatments on the precipitation behavior of Al3Zr dispersoids was investigated by transmission electron microscopy (TEM) in 7150 alloys. Two-step treatments with the first step in the temperature range of 300-400 degrees C followed by the second step at 470 degrees C were applied during homogenization. Compared with the conventional one-step homogenization, both a finer particle size and a higher number density of Al3Zr dispersoids were obtained with two-step homogenization treatments. The most effective dispersoid distribution was attained using the first step held at 300 degrees C. In addition, the two-step homogenization minimized the precipitate free zones and greatly increased the number density of dispersoids near dendrite grain boundaries. The effect of two-step homogenization on recrystallization resistance of 7150 alloys with different Zr contents was quantitatively analyzed using the electron backscattered diffraction (EBSD) technique. It was found that the improved dispersoid distribution through the two-step treatment can effectively inhibit the recrystallization process during the post-deformation annealing for 7150 alloys containing 0.04-0.09 wt.% Zr, resulting in a remarkable reduction of the volume fraction and grain size of recrystallization grains. (C) 2015 Elsevier Inc. All rights reserved.