Quench sensitivity and microstructure character of high strength AA7050  

7050高强铝合金淬火敏感性及组织特征(英文)

作　　者：李培跃[1,2] 熊柏青[2] 张永安[2] 李志辉[2] 朱宝宏[2] 王锋[2] 刘红伟[2] 

机构地区：[1]洛阳船舶材料研究所,洛阳471003 [2]北京有色金属研究总院有色金属材料及制各国家重点实验室,北京100088

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第2期268-274,共7页中国有色金属学报（英文版）

基　　金：Project (50904010) supported by the National Natural Science Foundation of China;Project (2010DFB50340) supported by the China International Science and Technology Cooperation

摘　　要：The effect of quenching rate on the electrical conductivity and microstructure of thick plates of incumbent AA7050 was investigated by employing Jominy end quench test. The electrical conductivity measurement and microstructural observation were conducted at different distances from the quenched end. The results indicate that the average cooling rates decrease with increasing the distance from the quenched end of the bar in the quench sensitive temperature range. However, the electrical conductivity increases with the increase of distance from the quenched end. The surface parts of the plate were fully recrystallized, while partial recrystallization took place at the quarter and center parts of the plate. The quench induced grain boundary precipitates became remarkably coarser and discontinuously distributed with increasing distance from the quenched end of the bar. Plenty of heterogeneous precipitates were observed to nucleate on A13Zr dispersoids when the distance from the quenched end was greater than 38mm.采用Jominy末端淬火实验研究淬火冷却速率对商用7050铝合金厚板淬火态合金电导率和组织的影响。实验测定距淬火端不同距离合金的淬火态电导率,并进行组织观察。结果表明:在淬火敏感区间范围内,合金的平均冷却速率随着淬火端距离的增加不断降低,而淬火态合金的电导率随着距离的增加不断上升。末端淬火实验棒组织观察显示,厚板表面已发生完全再结晶,1/4和1/2厚度处为部分再结晶组织,淬火诱导晶界析出相逐渐粗化并成链状分布,当距离大于38mm时,发现大量非均质形核淬火析出相,其形核核心主要为Al3Zr弥散相。

关 键 词：Jominy end quench test quench sensitivity cooling rate quench induced precipitates 

分 类 号：TG156.3[金属学及工艺—热处理]