7075铝合金的晶界特征分布及其对晶间腐蚀行为的影响

Grain boundary character distribution and its influence on intergranular corrosion behavior of 7075 aluminum alloy

摘要

7075铝合金极易发生晶间腐蚀(intergranular corrosion,IGC)和剥落腐蚀.为研究7075铝合金晶界特征分布(grain boundary character distribution,GBCD)对晶间腐蚀的影响,通过电子背散射衍射(electron back scatter diffraction,EBSD)技术对其晶界特征分布进行表征,借助金相显微镜观察其在25 ℃、pH=2、质量分数为3.5%的NaCl溶液中浸泡1.5、7 h后的腐蚀形貌.结果表明,随着浸泡时间的延长,7075铝合金的晶间腐蚀速率增加,其中大角度晶界的腐蚀增长速率最快.本研究明确了7075铝合金晶界特征分布与晶间腐蚀行为之间的相关性,为调控晶界结构和改善其耐蚀性能提供实验和理论依据.

Abstract

The 7075 aluminum alloy is susceptible to intergranular corrosion(IGC) and exfoliation corrosion.To investigate the effect of grain boundary character distribution(GBCD) of 7075 aluminum alloy on intergranular corrosion,the grain boundary character distribution was characterized by electron back scatter diffraction(EBSD).The corrosion morphologies were observed by metallurgical microscope after soaking in 3.5% NaCl solution(pH=2,25 ℃) for 1.5,7 h,respectively.The results showed that with the increase of soaking time,the intergranular corrosion rate of 7075 aluminum alloy increased,and the corrosion growth rate of large angle grain boundaries was the fastest.This study clarifies the correlation between the grain boundary character distribution and intergranular corrosion behavior in 7075 aluminum alloy,providing experimental and theoretical basis for regulating grain boundary structure and improving its corrosion resistance.

关键词

7075铝合金 / 晶界特征分布 / 电子背散射衍射 / 晶间腐蚀 / 耐蚀性

Key words

7075 aluminum alloy / grain boundary character distribution / electron back scatter diffraction / intergranular corrosion / corrosion resistance

参考文献

[1] Shen Y H, Zhang Y P, Liu X Y, et al. Enhanced long-term seawater corrosion resistance of 7075 Al via defect-sealing silane layer on rapidly deposited cathodic plasma electrolytic Al₂O₃ coating[J]. Ceramics International, 2025, 51(26):49734-49744.DOI:10.1016/j.ceramint.2025.08.212.

[2] Yang J D, Zhao Y T, Kai X Z, et al. Synergistic enhancement of in-situ (Al₂O₃+ZrB₂) nanoparticles and Er on microstructure and stress corrosion resistance of 7075 Al matrix composites[J]. Journal of Materials Research and Technology, 2025, 36:6542-6554.DOI:10.1016/j.jmrt.2025.04.287.

[3] 沈耀红. 冷轧与热处理对7075铝合金微观组织结构的影响[D]. 重庆: 重庆大学, 2011.

[4] Shen Yaohong. The influence on the microstructure of 7075 aluminum alloy during cold-rolled and heat treatment[D]. Chongqing: Chongqing University, 2011.

[5] Watanabe T. An approach to grain boundary design for strong and ductile polycrystals[J]. 1984, 11(1):47-84.

[6] Jia Z P, Guan X J, Wang D Q Q, et al. A novel surface grain boundary engineering approach to improving corrosion resistance of a high-N and Ni-free austenitic stainless steel[J]. Corrosion Science, 2024, 233:112110.DOI:10.1016/j.corsci.2024.112110.

[7] Shi F, Tian P C, Jia N, et al. Improving intergranular corrosion resistance in a nickel-free and manganese-bearing high-nitrogen austenitic stainless steel through grain boundary character distribution optimization[J]. Corrosion Science, 2016, 107:49-59.DOI:10.1016/j.corsci.2016.02.019.

[8] Liang H L, Dong N, Zhang C L, et al. Enhancing the corrosion resistance of high Mo S31254 super austenitic stainless steel using grain boundary engineering[J]. Materials Today Communications, 2024, 39:109196.DOI:10.1016/j.mtcomm.2024.109196.

[9] Prithiv T S, Bhuyan P, Pradhan S K, et al. A critical evaluation on efficacy of recrystallization vs. strain induced boundary migration in achieving grain boundary engineered microstructure in a Ni-base superalloy[J].Acta Materialia, 2018, 146:187-201.DOI:10.1016/j.actamat.2017.12.045.

[10] Zhang C C, Lu Z, Chu G N, et al. Recrystallization behavior and grain boundary character evolution in an additively manufactured Ni-based GH4099 alloy during heat treatment[J]. Journal of Alloys and Compounds, 2025, 1026:180465.DOI:10.1016/j.jallcom.2025.180465.

[11] Hu H L, Li J W, He W W, et al. Effects of thermo-mechanical processing on the microstructure of Inconel 617 alloy[J]. Materials Today Communications, 2025, 42:111574.DOI:10.1016/j.mtcomm.2025.111574.

[12] Wang Z G, Song C M, Zhang Y H, et al. Effects of yttrium addition on grain boundary character distribution and stacking fault probabilities of 90Cu10Ni alloy[J]. Materials Characterization, 2019, 151:112-118.DOI:10.1016/j.matchar.2019.02.040.

[13] Chen Z P, Yang Y, Lou H F, et al. Effect of thermomechanical processing on the grain boundary character distribution of phosphorus bronze[J]. Materials Characterization, 2024, 217:114401.DOI:10.1016/j.matchar.2024.114401.

[14] Guan X J, Shi F, Ji H M, et al. Gain boundary character distribution optimization of Cu-16at.%Al alloy by thermomechanical process:critical role of deformation microstructure[J].Materials Science and Engineering:A, 2019, 765:138299.DOI:10.1016/j.msea.2019.138299.

[15] Wang C, Yin J, He J Y, et al. Effect of grain boundary engineering on electrochemical and intergranular corrosion of 316L stainless steel[J]. Corrosion Science, 2025, 254:113050.DOI:10.1016/j.corsci.2025.113050.

[16] Xia S, Zhou B X, Chen W J. Effect of single-step strain and annealing on grain boundary character distribution and intergranular corrosion in alloy 690[J]. Journal of Materials Science, 2008, 43(9):2990-3000.DOI:10.1007/s10853-007-2164-y.

[17] 姜涛, 付少利, 董健龙. B10白铜晶界特征分布对耐腐蚀性能的影响[J]. 有色金属材料与工程, 2023, 44(1):15-23.DOI:10.13258/j.cnki.nmme.2023.01.003.

[18] Jiang Tao, Fu Shaoli, Dong Jianlong. Effect of grain boundary characteristic distribution on corrosion resistence performance of B10 cupronickel[J]. Nonferrous Metal Materials and Engineering, 2023, 44(1):15-23.

[19] Kim S H, Erb U, Aust K T, et al. Grain boundary character distribution and intergranular corrosion behavior in high purity aluminum[J]. Scripta Materialia, 2001, 44(5):835-839.DOI:10.1016/S1359-6462(00)00682-5.

[20] Mondou E, Proietti A, Charvillat C, et al. Understanding the mechanisms of intergranular corrosion in 2024 Al alloy at the polycrystal scale[J]. Corrosion Science, 2023, 221:111338.DOI:10.1016/j.corsci.2023.111338.

[21] Birbilis N, Buchheit R G. Electrochemical characteristics of intermetallic phases in aluminum alloys[J]. Journal of the Electrochemical Society, 2005, 152(4):B140.DOI:10.1149/1.1869984.

[22] Svenningsen G, Larsen M H, Walmsley J C, et al. Effect of artificial aging on intergranular corrosion of extruded AlMgSi alloy with small Cu content[J]. Corrosion Science, 2006, 48(6):1528-1543.DOI:10.1016/j.corsci.2005.05.045.

[23] Song F X, Zhang X M, Liu S D, et al. The effect of quench transfer time on microstructure and localized corrosion beha-vior of 7050-T6 Al alloy[J]. Materials and Corrosion, 2014, 65(10):1007-1016.DOI:10.1002/maco.201307192.

基金资助

国家自然科学基金(51171118)

河北师范大学博士科研启动基金(L2023B52)