采用透射电镜(TEM)和维氏硬度计研究了回归再时效 (RRA)处理对7050合金的的影响.研究发现,7050合金受回归温度和时间影响.当回归温度为453K和473K时,回归曲线由三部分组成,回归再时效曲线由两部分组成.与在回归曲线上存在的峰值硬度相比,回归再时效峰值硬度要高.TEM观察表明,硬度谷值的产生与GP 区的回溶有关,而峰值的产生与η′和η相的沉淀析出有关.回归再时效峰值高于回归峰值,这与回归再时效过程中η和η′相沉淀析出数目增加有关.当回归温度为493K, 回归和回归再时效曲线单调下降,分析认为由于回归温度高,回归曲线上不能区分GP区的回溶、η和η′相形核、η和η′相长大及粗化这三个阶段.
参考文献
| [1] | HUNSICKER H Y.The Metals Society[A].London UK,1975:245-262. |
| [2] | BURLEIGH T D .Postulated mechanisms for stress corrosion cracking of aluminum alloys. A review of the literature 1980-1989,1991[J].Corrosion,1991,47(02):89-98. |
| [3] | NAJJAR D;MAGMIN T;WARNER T J .Influence of critical surface defects and localized competition between[J].Materials Science and Engineering A,1997,238:293-302. |
| [4] | CINA B .Reducing the susceptibility of alloy,particularly aluminum alloys to stress corrosion cracking[P].USP:3856584,1974. |
| [5] | PARK J K;ARDELL A J .Effect of retrogression and reaging treatments on the microstructure of Al-7050-T651[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1984,15:1531-1543. |
| [6] | OHINISHI T;IBARAKJ Y;ITO T .Improvement of fracture toughness in 7475 aluminum alloy by the RRA process[J].Materials Transactions,1989,8:601-607. |
| [7] | LUKASAK D A;HART R M .Aluminum alloy development[J].Journal of Aerospace Engineering,1991,11(09):21-24. |
| [8] | RAJAN K;WALLACE W;BEDDOES J C .Microstructural study of a high-strength stress-corrosion resistant 7075 aluminium alloy[J].Journal of Materials Science,1982,17:2817-2825. |
| [9] | DANH N C;RAJAN K;WALLACE W .A TEM study of microstructural changes during retrogression and reaging in 7075 Aluminum[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1983,14:1843-1850. |
| [10] | DEGISCHER H P;LACOM W;ZAHRA A;ZAHRA C Y .Decomposition processes in an Al-5%Zn-1%Mg alloy[J].Metallkd,1980,71:231-238. |
| [11] | DEELASI R;ACLLER P N .Calormetric studies of 7000 series Aluminum alloys matrix precipitate characterization of 7075[J].Metallurgical and Materials Transactions,1977,8:1177-1190. |
| [12] | LLOYD D J;CHATURVEDI M C .A calorimetric study of aluninum alloy AA-7075[J].Journal of Materials Science,1983,17:1819-1825. |
| [13] | LORIMER G W;NICHOLSON R B .Further result on the nucleation of precipitatess in the Al-Zn-Mg system[J].Acta Materialia,1966,14:1009. |
| [14] | CORNISON A J;DAY M K B .Precipitation in the neighbourhood of grain boundaries in an Al-Zn-Mg alloy[J].Journal of The Institute of Metals,1969,97:44-52. |
| [15] | HUANG Z W;LORETTO M H;WHITE J .Influence of lithiun additions on precipitation and age hardening of 7075 alloy[J].Materials Science and Technology,1993,9:867-980. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%