时效温度对7055铝合金晶间腐蚀敏感性的影响  

Effect of aging temperature on intergranular corrosion susceptibility of 7055 aluminum alloy

作　　者：朱聪 王芝秀 王烨[1] 李海 Zhu Cong;Wang Zhixiu;Wang Ye;Li Hai(School of Materials Science and Engineering,Changzhou University,Changzhou Jiangsu 213164,China;Jiangsu Key Laboratory of Materials Surface Science and Technology Changzhou University,Changzhou Liangsu 213164,China)

机构地区：[1]常州大学材料科学与工程学院,江苏常州213164 [2]常州大学江苏省材料表面科学与技术重点实验室,江苏常州213164

出　　处：《金属热处理》2025年第1期206-212,共7页Heat Treatment of Metals

基　　金：国家自然科学基金(52171029,51671038)。

摘　　要：采用光学显微镜(OM)、透射电镜(TEM)、硬度测试、晶间腐蚀测试等方法研究了时效温度(150、180、210℃)对喷射成形7055铝合金晶间腐蚀敏感性的影响。结果表明,在相同硬度条件下,欠时效合金发生晶间腐蚀,而峰时效及过时效合金发生点蚀。随着时效温度的升高和时效时间的延长,合金晶间腐蚀敏感性降低,腐蚀形貌由晶间腐蚀向点蚀转变。时效温度由150℃提高至210℃,晶界析出相(GBPs)由连续分布向断续分布转变,GBPs中的Cu含量从3.82%升高至5.02%,无沉淀析出带(PFZs)宽度从37 nm增加到55 nm。合金晶间腐蚀敏感性的变化源于GBPs的粗大且不连续分布、PFZs宽度的增加以及GBPs中Cu元素偏聚的共同作用。Effect of aging temperature(150,180,210 ℃) on intergranular corrosion susceptibility of 7055 aluminum alloy was studied by means of optical microscope(OM),transmission electron microscope(TEM),hardness test and intergranular corrosion test.The results show that under the same hardness condition,intergranular corrosion occurs in the under-aged alloy,while pitting corrosion occurs in the peak-aged and over-aged alloys.With the increase of aging temperature and time,the intergranular corrosion susceptibility of the alloy decreases and the corrosion morphology changes from intergranular corrosion to pitting corrosion.With the aging temperature increasing from 150 ℃ to 210 ℃,the grain boundary precipitates(GBPs) change from continuous distribution to discontinuous distribution,the Cu content in GBPs increases from 3.82% to 5.02%,and the width of precipitate free zones(PFZs) increases from 37 nm to 55 nm.The change of intergranular corrosion susceptibility of the alloy is due to the combined effect of coarsening and discontinuous distribution of GBPs,the broadening of PFZs,and the segregation of Cu element in GBPs.

关 键 词：7055铝合金 时效温度 微观组织 晶间腐蚀敏感性 

分 类 号：TG146.21[一般工业技术—材料科学与工程]