SMALL CRACK-GROWTH IN THE ALUMINUM LITHIUM ALLOYS 8090 AND 8091

被引：11

作者：

NICHOLLS, DJ

MARTIN, JW

机构：

[1] Department of Metallurgy and the Science of Materials, Oxford University, Oxford

来源：

FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES | 1990年 / 13卷 / 01期

关键词：

D O I：

10.1111/j.1460-2695.1990.tb00578.x

中图分类号：

TH [机械、仪表工业];

学科分类号：

0802 ;

摘要：

The relationship between microstructure and the fatigue behaviour of small cracks has been examined for the aluminium–lithium alloys 8090 and 8091 after peak ageing at 170°C. Duplex ageing and pre‐stretching were used to vary the distribution of S'precipitates and thus the distribution of slip. No effect of S'distribution an small crack growth was observed in either alloy. This is thought to be due to a combination of the lack of closure and lower overall slip reversibility in small cracks. Small cracks in 8091 were found to grow slower than in 8090 due to differences in grain shape rather than texture. Small cracks in both alloys were observed to grow much faster than long cracks for equivalent ΔKs. This difference was reduced when small crack data were compared with long crack data generated at R= 0.7 due to the reduced closure. The use of ΔJ made long and small crack growth rates still more comparable. Copyright © 1990, Wiley Blackwell. All rights reserved

引用

页码：83 / 94

页数：12

共 24 条

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