Si含量对7050铝合金显微组织和抗应力腐蚀开裂的影响(英文)

• 作 者: 佘欢 储威 疏达 王俊 孙宝德
• 机 构: 上海交通大学上海市先进高温材料及其精密成形重点实验室,上海交通大学金属基复合材料国家重点实验室,
• 出 处: Transactions of Nonferrous Metals Society of China
• 发表日期: 2014年07期
• 关键词: 应力腐蚀开裂 铝合金 慢应变速率拉伸 7050铝合金 Si含量 显微组织 SSRT cracking tensile coarse

分别研究Si含量为0.094%、0.134%和0.261%的3种T7651态7050铝合金的组织和应力腐蚀开裂敏感性。结果表明:随着Si含量从0.094%增加到0.261%,Mg2Si相的面积分数从0.16%增加到1.48%,并且尺寸粗化;而其它粗大相(包括Al2CuMg、Mg(Al,Cu,Zn)2和Al7Cu2Fe)的面积分数从2.42%减小到0.78%。合金的电导率随Si含量的增加而增加。合金在空气中进行慢应变速率拉伸时,抗拉强度和伸长率随Si含量的增加而降低;而在3.5%NaCl溶液中进行慢应变速率拉伸时,随Si含量增加,合金应力腐蚀开裂敏感性降低。

The microstructure and stress corrosion cracking susceptibility of three kinds of T7651 7050 aluminum alloy with Si content of 0.094%, 0.134% and 0.261% were studied respectively. The results show that as the Si content increases from 0.094% to 0.261%, the area fraction of Mg2Si phase increases from 0.16% to 1.48% and the size is coarsened. The other coarse phases (including Al2CuMg, Mg (Al, Cu, Zn) And Al7Cu2Fe) decreased from 2.42% to 0.78%. The conductivity of the alloy increases with increasing Si content. Tensile strength and elongation decrease with increasing Si content when the alloy is stretched in air at a slow strain rate. When the alloy is stretched at a slow strain rate in 3.5% NaCl solution, the stress corrosion cracking Sensitivity reduced.