T6和T78时效工艺对Al-Mg-Si-Cu合金显微结构和性能的影响

doi:10.3724/SP.J.1037.2012.00509

金属学报

2013, Vol. 49

Issue (2): 243-250 DOI: 10.3724/SP.J.1037.2012.00509

论文

本期目录 | 过刊浏览

T6和T78时效工艺对Al-Mg-Si-Cu合金显微结构和性能的影响

李祥亮，陈江华，刘春辉，冯佳妮，王时豪

湖南大学材料科学与工程学院, 长沙 410082

EFFECTS OF T6 AND T78 TEMPERS ON THE MICROSTRUCTURES AND PROPERTIES OF Al－Mg－Si－Cu ALLOYS

LI Xiangliang, CHEN Jianghua, LIU Chunhui, FENG Jiani, WANG Shihao

College of Materials Science and Engineering, Hunan University, Changsha 410082

引用本文:

李祥亮，陈江华，刘春辉，冯佳妮，王时豪. T6和T78时效工艺对Al-Mg-Si-Cu合金显微结构和性能的影响[J]. 金属学报, 2013, 49(2): 243-250.
LI Xiangliang, CHEN Jianghua, LIU Chunhui, FENG Jiani, WANG Shihao. EFFECTS OF T6 AND T78 TEMPERS ON THE MICROSTRUCTURES AND PROPERTIES OF Al－Mg－Si－Cu ALLOYS[J]. Acta Metall Sin, 2013, 49(2): 243-250.

全文: PDF(3585 KB)

摘要:

借助显微硬度测试、电导率测试、浸泡腐蚀实验、SEM, TEM和元素面扫描, 研究了T6和T78时效工艺对Al－0.75Mg－0.75Si－0.8Cu(质量分数, %)合金显微结构和性能的影响. 结果表明, 实验合金在T6峰值时效(180 ℃, 8 h)时, 硬度为128.3 HV, 电导率为27.3~10⁶ S/m. 在T6(180 ℃, 5 h)基础上, 分别进行温度为195, 205和215 ℃的二级时效,即T78时效工艺, 随二级时效时间的延长, 合金硬度总体变化趋势为先降低后升高, 而电导率值逐渐增大; 最佳T78工艺为 (180 ℃,5 h)+(195 ℃, 2 h), 此时合金的硬度最高, 为129.2 HV, 电导率为27.610⁶ S/m. TEM观察发现, T6峰值时效时,晶粒内主要析出针状的β”相, 经T78双级时效处理后, 晶粒内析出大量的板条状析出相, 而晶界无析出带仅稍有变化. T78工艺能在保持力学性能的同时, 大幅提高耐晶间腐蚀性能, 其原因是晶粒内形成了表面有Cu富集的板条状析出相.晶粒内析出大量板条状强化相, 使得合金硬度与T6峰值相当, 同时Cu偏聚在析出相与Al基体界面处, 促使更多Al基体中的Cu析出,基体与无析出带(PFZ)电位差大大降低, 使得其抗晶间腐蚀性能大大提高.

关键词 ：铝合金, 析出相, 晶界, 晶间腐蚀, 显微结构

Abstract：

Although AlMgSi (6000－series) are generally considered to have better corrosion resistance than other aluminum alloys, it may introduce susceptibility to intergranular corrosion (IGC) by some factors, for instance, improper thermo－mechanical treatment and high Cu content. So the T78 treatment has been designed to desensitize it to IGC. In this paper, effects of T6 and T78 tempers on the microstructures and properties of an Al－0.75Mg－0.75Si－0.8Cu (mass fraction, %) were investigated by hardness test, electric conductivity test,accelerated corrosion test, SEM, TEM and energy dispersive X－ray elemental mapping. The hardness and conductivity of the T6 peak－aged sample, which was obtained by artificial aging for 8 h at 180 ℃, were 128.3 HV and 27.3~10⁶ S/m, respectively. T78 tempers involved a first step aging (180 ℃, 5 h) followed by a second step aging at 195, 205 and 215 ℃, respectively.With the prolonging of second step aging, the hardness firstly decreased then increased, while the conductivity increased gradually. The optimum T78 process was(180 ℃, 5 h)+(195 ℃, 2 h), at which condition the hardness was 129.2 HV and the electric conductivity was 27.6~10⁶ S/m. TEM observation results show that it was mostly needle－likeβ” phase in the Al matrix for the peak－aged sample. After T78 treatment, a large amount of lath－like precipitates formed in the matrix, while the precipitate free zones (PFZ) broadened slightly. The segregation of Cu was found at the interface between lath－like precipitates and the matrix, so more Cu precipitated out from the Al matrix and thus reduced the electrochemical potential difference between the PFZ and the matrix. The above finding may explain why T78 temper can desensitize intergranular corrosion without sacrificing strength.

Key words： aluminum alloy precipitate grain boundary intergranular corrosion, microstructure

收稿日期: 2012-08-31

基金资助:

国家重点基础研究发展计划项目2009CB623704, 国家自然科学基金项目51171063,湖南省高校科技创新团队项目, 湖南省研究生科研创新项目和Gatan中国博士生奖学金项目资助

作者简介: 李祥亮, 男, 1987年生, 硕士生

	服务

	把本文推荐给朋友
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	李祥亮
	陈江华
	刘春辉
	冯佳妮
	王时豪
44.8K

链接本文:

https://www.ams.org.cn/CN/10.3724/SP.J.1037.2012.00509 或 https://www.ams.org.cn/CN/Y2013/V49/I2/243

[1] Chen J H, Liu C H. Trans Nonferrous Met Soc China, 2011; 21: 2352

(陈江华, 刘春辉. 中国有色金属学报, 2011; 21: 2352)

[2] Chen J H, Costan E, Van Huis M A, Xu Q, Zandbergen H W. Science, 2006; 312: 416

[3] Guinier A. Nature, 1938; 142: 570

[4] Tian N, Zhao G, Zuo L, Liu C M. Acta Metall Sin, 2010; 46: 613

(田妮, 赵刚, 左良, 刘春明. 金属学报, 2010; 46: 613)

[5] Liu Y N, Chen J H, Yin M J, Liu C H, Wu C L, Zhao X Q. J Chin Electron Microsc Soc, 2010; 29: 280

(刘亚妮, 陈江华, 尹美杰, 刘春辉, 伍翠兰, 赵新奇. 电子显微学报, 2010; 29: 280)

[6] Zhan H, Mol J M C, Hannour F, Zhuang L, Terryn H. Mater Corros, 2008; 59: 670

[7] Larsen M H, Walmsley J C, Lunder O T, Nisancioglu K. Mater Sci Forum, 2006; 519: 667

[8] Dif R, Bes B, Warner T, Lequeu P, Ribes H, Lassinccp P. Advances in the Metallurgy of Aluminum Alloys. Ohio: AMS International Publications, 2001: 390

[9] Williams J C, Starke E A. Acta Mater, 2003; 51: 5775

[10] Tanaka M, Warner T. Mater Sci Forum, 2000; 331: 983

[11] Shi A, Shaw B A, Sikora E. Corros Sci Sect, 2005; 61: 534

[12] Sinyavskii V S, Ulanova V V, Kalinin V D. Prot Met, 2004; 40: 537

[13] Liao Y F, Chen J H, Liu C H, Li X L, Feng J N. J Chin Electron Microsc Soc, 2012; 31: 116

(廖元飞, 陈江华, 刘春辉, 李祥亮, 冯佳妮. 电子显微学报, 2012; 31: 116)

[14] Vukmirovic M B, Dimitrov N, Sieradzk K. J Electrochem Soc, 2002; 149: B428

[15] Svenningsen G, Larsen M H, Walmsley J C, Nordlien J H, Nisancioglu K. Corros Sci, 2006; 48: 1528

[16] Li H , Pan D Z, Wang Z X, Zheng Z Q. Acta Metall Sin, 2010; 46: 494

(李海, 潘道召, 王芝秀, 郑子樵. 金属学报, 2010; 46: 494)

[17] Zandbergen H W, Andersen S J, Jansen J. Science, 1997; 277: 1221

[18] Marioara C D, Andersen S J, Stene T N, Hasting H, Walmsley J C, Van Heelvort A T J, Holmestad R. Philos Mag, 2007; 87: 3385

[19] Chakrabarti D J, Laughlin D E. Prog Mater Sci, 2004; 49: 389

[20] Tors{\aeter M, Lefebvre W, Marioara C D, Andersen S J, Walmsley J C, Holmestad R. Scr Mater, 2011; 64: 817

[21] Arnberg L, Aurivillius B. Acta Chem Scand Ser A, 1980; 34: 1

[22] Wang X, Esmaeili S, Lloyd D J. Metall Mater Trans, 2006; 37A: 2691

[23] Hasting H S, Walmsley J C, Van Helvoort A T J, Marioara C D, Andersen S J, Holmestad R. Philos Mag Lett, 2006; 86: 589

[24] Van Huis M A, Chen J H, Zandbergen H W, Sluiter M H F. Acta Mater, 2006; 54: 2945

[25] Esmaeili S, Vaumousse D, Zandbergen M W, Poole W J, Cerezo A, Lloyd D J. Philos Mag, 2007; 87: 3797

[1]	常松涛, 张芳, 沙玉辉, 左良. 偏析干预下体心立方金属再结晶织构竞争[J]. 金属学报, 2023, 59(8): 1065-1074.
[2]	张海峰, 闫海乐, 方烽, 贾楠. FeMnCoCrNi高熵合金双晶微柱变形机制的分子动力学模拟[J]. 金属学报, 2023, 59(8): 1051-1064.
[3]	徐永生, 张卫刚, 徐凌超, 但文蛟. 铁素体晶间变形协调与硬化行为模拟研究[J]. 金属学报, 2023, 59(8): 1042-1050.
[4]	李福林, 付锐, 白云瑞, 孟令超, 谭海兵, 钟燕, 田伟, 杜金辉, 田志凌. 初始晶粒尺寸和强化相对GH4096高温合金热变形行为和再结晶的影响[J]. 金属学报, 2023, 59(7): 855-870.
[5]	王宗谱, 王卫国, Rohrer Gregory S, 陈松, 洪丽华, 林燕, 冯小铮, 任帅, 周邦新. 不同温度轧制Al-Zn-Mg-Cu合金再结晶后的{111}/{111}近奇异晶界[J]. 金属学报, 2023, 59(7): 947-960.
[6]	梁凯, 姚志浩, 谢锡善, 姚凯俊, 董建新. 新型耐热合金SP2215组织与性能的关联性[J]. 金属学报, 2023, 59(6): 797-811.
[7]	杨杜, 白琴, 胡悦, 张勇, 李志军, 蒋力, 夏爽, 周邦新. GH3535合金中晶界特征对碲致脆性开裂影响的分形分析[J]. 金属学报, 2023, 59(2): 248-256.
[8]	李昕, 江河, 姚志浩, 董建新. O原子对高温合金基体Ni、Co和NiCr晶界作用的理论计算分析[J]. 金属学报, 2023, 59(2): 309-318.
[9]	夏大海, 计元元, 毛英畅, 邓成满, 祝钰, 胡文彬. 2024铝合金在模拟动态海水/大气界面环境中的局部腐蚀机制[J]. 金属学报, 2023, 59(2): 297-308.
[10]	陈凯旋, 李宗烜, 王自东, Demange Gilles, 陈晓华, 张佳伟, 吴雪华, Zapolsky Helena. Cu-2.0Fe合金等温处理过程中富Fe析出相的形态演变[J]. 金属学报, 2023, 59(12): 1665-1674.
[11]	芮祥, 李艳芬, 张家榕, 王旗涛, 严伟, 单以银. 新型纳米复合强化9Cr-ODS钢的设计、组织与力学性能[J]. 金属学报, 2023, 59(12): 1590-1602.
[12]	马国楠, 朱士泽, 王东, 肖伯律, 马宗义. SiC颗粒增强Al-Zn-Mg-Cu复合材料的时效行为和力学性能[J]. 金属学报, 2023, 59(12): 1655-1664.
[13]	刘路军, 刘政, 刘仁辉, 刘永. Nd₉₀Al₁₀ 晶界调控对晶界扩散磁体磁性能和微观结构的影响[J]. 金属学报, 2023, 59(11): 1457-1465.
[14]	高建宝, 李志诚, 刘佳, 张金良, 宋波, 张利军. 计算辅助高性能增材制造铝合金开发的研究现状与展望[J]. 金属学报, 2023, 59(1): 87-105.
[15]	马志民, 邓运来, 刘佳, 刘胜胆, 刘洪雷. 淬火速率对7136铝合金应力腐蚀开裂敏感性的影响[J]. 金属学报, 2022, 58(9): 1118-1128.

Viewed

Full text

Abstract

Cited

Shared

Discussed