Growth Mechanism of a Fatigue Crack of Age-hardened Al Alloy in High humidity
Effect of humidity on the growth mechanism of a fatigue crack in an age-hardened A1 alloy was investigated in relative humidity of 25% and 85% at loading frequencies of 50 and 6Hz.Macroscopic growth mode of a crack in low humidity was a tensile one irrespective of loading frequency.By contrast, the mode in high humidity was changed from the shear one to the tensile one with increase in fatigue life at 50 Hz, while it was the tensile mode only at 6 Hz.In low humidity, the crack propagated by forming striations which are general in fatigue of many metals.On the other hand, in high humidity, most of fracture surface was occupied by many slip planes in the shear mode crack and by granular facets in addition to striations in the tensile mode one.The difference in growth mechanism of a crack was explained by the microstructure with sub-grain and texture and the cyclic softening behavior of the alloy and hydrogen content.
Fatigue High strength Al alloy Humidity Crack growth mechanism Hydrogen embrittlement
N.Kawagoishi K.Kariya QY.Wang Q.Chen XS.Wang
Dai-ichi Institute of Technology, Kirishima, Japan Sichuan University, Chengdu, China Kumamoto University, Kumamoto, Japan Tsinghua University, Beijing, China
国际会议
北京
英文
53-60
2014-10-19（万方平台首次上网日期，不代表论文的发表时间）