Journal of Jilin University(Engineering and Technology Edition) ›› 2019, Vol. 49 ›› Issue (5): 1636-1643.doi: 10.13229/j.cnki.jdxbgxb20180343

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Effect of creep and artificial aging on fatigue crack growth performance of 2524 aluminum alloy

Yi-lun LIU1,2(),Qing WANG1,Chi LIU1,Song-bai LI1,Jun HE1,Xian-qiong ZHAO1   

  1. 1. College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China
    2. Light Alloy Research Institute, Central South University, Changsha 410083, China
  • Received:2018-04-13 Online:2019-09-01 Published:2019-09-11

Abstract:

The effects of creep aging and artificial aging on the fatigue crack propagation properties of 2524 aluminum alloy were investigated. The influence of aging conditions on the fatigue properties of the alloy was analyzed based on the microstructure evolution of the alloy under TEM. The results show that the microstructures of artificial aging and creep aging alloys are mainly Cu-Mg clusters and GPB zones after aging for 4 h, showing good fatigue resistance. Compared with 4 h, after aging for 9 h the microstructures of the alloy are mainly acicular S′ phase. The appearance of these coarse S′ phases changes the slip mode of dislocation, which reduces the reversibility of slip and accelerates the accumulation of fatigue damage. Near the threshold section of Δ K 7 ? M P a · m 1 2 , the alloy fatigue resistance decreases significantly. The precipitate free zone appears at the grain boundary of the alloy after aging for 24 h, and the precipitates in the grain are also larger in size, further accelerating the fatigue crack growth rate of the alloy. Creep stress accelerates the precipitation process of alloy and compared with artificial aging, the creep aging alloy has larger precipitate size, higher yield strength and hardness, but lower fatigue resistance at the same aging time.

Key words: aerospace materials, fatigue crack propagation, fracture mechanics, 2524 aluminum alloy, creep aging, precipitate

CLC Number: 

  • TG146.2

Fig.1

Creep aging forming experiment schematic diagram"

Fig.2

Compact tensile sample (CT sample)"

Fig.3

TEM images of 2524 aluminum alloy under different treatment processes"

Fig.4

Diffraction patterns of 2524 aluminum alloy under different treatment processes"

Fig.5

Grain boundary TEM images of 2524 aluminum alloy under different treatment processes"

Fig.6

Mechanical properties of 2524 aluminum alloy under different aging conditions"

Fig.7

Fatigue crack growth rates of 2524 aluminum alloys under different creep aging times"

Fig.8

Fatigue crack growth rates of 2524 aluminum alloys under different aging conditions"

1 Nakai M , Eto T . New aspects of development of high strength aluminum alloys for aerospace applications[J]. Materials Science and Engineering A, 2000, 285(1-5): 62-68.
2 Starke E , Staley J T . Application of modern aluminum alloys to aircraft[J]. Progress in Aerospace Sciences, 1996, 32(2): 131-172.
3 Warner T . Recently-developed aluminium solutions for aerospace applications[J]. Materials Science Forum, 2006(519-521): 1271-1278.
4 Zeng Y , Huang X . Forming technologies of large integral panel[J]. Acta Aeronautica Et Astronautica Sinica, 2008, 29(3): 721-727.
5 Zhan L , Lin J , Dean T A . A review of the development of creep age forming: experimentation, modelling and applications[J]. International Journal of Machine Tools & Manufacture, 2011, 51(1): 1-17.
6 Jeunechamps P P , Ho K C , Lin J , et al . A closed form technique to predict springback in creep age-forming[J]. International Journal of Mechanical Sciences, 2006, 48(6): 621-629.
7 Zhan L , Lin J , Dean T A , et al . Experimental studies and constitutive modelling of the hardening of aluminium alloy 7055 under creep age forming conditions[J]. International Journal of Mechanical Sciences, 2011, 53(8): 595-605.
8 Zhang J , Zhang S N , Liang E W . Blazar Anti-Sequence of spectral variation within individual blazars: cases for Mrk 501 and 3C 279[J]. The Astrophysical Journal, 2013(767): 1-7.
9 Jeshvaghani R A , Zohdi H , Shahverdi H R , et al . Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: optimization for springback, strength and exfoliation corrosion[J]. Materials Characterization, 2012, 73(11): 8-15.
10 Xu Y , Zhan L , Li W . Effect of pre-strain on creep aging behavior of 2524 aluminum alloy[J]. Journal of Alloys & Compounds, 2017, 691: 564-571.
11 Yin D , Liu H , Chen Y , et al . Effect of grain size on fatigue-crack growth in 2524 aluminium alloy[J]. International Journal of Fatigue, 2016, 84: 9-16.
12 Srivatsan T S , Kolar D , Magnusen P . The cyclic fatigue and final fracture behavior of aluminum alloy 2524[J]. Materials & Design, 2002, 23(2): 129-139.
13 Baptista C A R P , Adib A M L , Torres S , et al . Describing fatigue crack growth and load ratio effects in Al 2524 T3 alloy with an enhanced exponential model[J]. Mechanics of Materials, 2012, 51: 66-73.
14 Shih H C , Ho N J , Huang J C . Precipitation behaviors in Al-Cu-Mg and 2024 aluminum alloys[J]. Metallurgical & Materials Transactions A, 1996, 27(9): 2479-2494.
15 Bagaryatsky Y A . Structural changes on aging Al-Cu-Mg alloys[J]. Doklady Akademii nauk SSSR, 1952, 87(3): 397-559.
16 Chen Y Q , Yi D Q , Jiang Y , et al . Twinning and orientation relationships of T-phase precipitates in an Al matrix[J]. Journal of Materials Science, 2013, 48(8): 3225-3231.
17 Chen Z , Chen P , Li S . Effect of Ce addition on microstructure of Al20Cu2Mn3 twin phase in an Al-Cu-Mn casting alloy[J]. Materials Science & Engineering A, 2012, 532: 606-609.
18 刘义伦, 羿九火, 杨大炼, 等 . 固溶温度对7075铝合金组织及高周疲劳性能的影响[J]. 金属热处理, 2016, 41(3): 1-7.
Liu Yi-lun , Yi Jiu-huo , Yang Da-lian , et al . Effects of solution treatment on microstructure and high cycle fatigue properties of 7075 aluminum alloy[J]. Heat Treatment of Metals, 2016, 41(3): 1-7.
19 陈宇强, 潘素平, 刘文辉, 等 . 析出相对Al-Cu-Mg合金蠕变行为的影响[J]. 中国有色金属学报, 2015, 25(4): 900-909.
Chen Yu-qiang , Pan Su-ping , Liu Wen-hui , et al . Effect of precipitates on creep behaviors of Al-Cu-Mg alloy [J]. The Chinese Journal of Nonferrous Metals, 2015, 25(4): 900-909.
20 Ringer S P , Sakurai T , Polmear I J . Origins of hardening in aged Al-Cu-Mg-(Ag) alloys[J]. Acta Materialia, 1997, 45(9): 3731-3744.
21 湛利华, 李炎光, 黄明辉 . 应力作用下2124合金蠕变时效的组织与性能[J]. 中南大学学报:自然科学版, 2012, 43(3): 926-931.
Zhan Li-hua , Li Yan-guang , Huang Ming-hui . Microstructures and properties of 2124 alloy creep ageing under stress[J]. Journal of Central South University (Science and Technology), 2012, 43(3): 926-931.
22 汤华国, 马贤锋, 赵伟, 等 . 高性能金属铝的制备、微观结构及其热稳定性[J]. 吉林大学学报: 工学版, 2017, 47(5): 1542-1547.
Tang Hua-guo , Ma Xian-feng , Zhao Wei , et al . Synthesis microstructure and thermal properties of high performance bulk Al[J]. Journal of Jilin University (Engineering and Technology Edition), 2017, 47(5): 1542-1547.
23 杨悦, 陈彬 . SiC纳米颗粒对6060型铝合金微弧氧化膜组织结构及耐蚀性能的影响[J]. 吉林大学学报: 工学版, 2011, 41(增刊1): 106-110.
Yang Yue , Chen Bin . Effects of SiC nano-particles on microstructure and the corrosion resistance of micro-arc oxidation films produced on aluminium alloy[J]. Journal of Jilin University (Engineering and Technology Edition), 2011, 41(Sup.1): 106-110.
24 Krol T , Baither D , Nembach E . The formation of precipitate free zones along grain boundaries in a superalloy and the ensuing effects on its plastic deformation[J]. Acta Materialia, 2004, 52(7): 2095-2108.
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