Study on Initiation and Growth of Fatigue Crack of Pre-corroded 7B04 Aluminium Alloy Specimen

2nd International Conference on Frontiers of Materials Synthesis and Processing

Qian, Ang^1 ; Tan, Xiaoming^1 ; Wang, De^1 ; You, Mingrui^1

Qingdao Branch, Naval Aeronautical University, Qingdao

266041, China^1

关键词: Corrosion damage;    Corrosion pits;    Crack propagation path;    Fatigue crack initiation;    Fatigue cracks;    High strength aluminum alloys;    Main bearings;    Single edge notched specimens;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/493/1/012022/pdf
DOI  :  10.1088/1757-899X/493/1/012022

来源: IOP

【 摘 要 】

The purpose is to study the fatigue crack initiation and propagation behavior of aluminum alloy under pre corrosive damage. The high strength aluminum alloy 7B04-T74 with main bearing structure of aircraft was used to prepare single edge notched specimens for pre corrosion and fatigue tests, and the effects of corrosion damage on fatigue crack initiation and propagation are analyzed. It is found that the fatigue crack sprout at the bottom of a single corrosion pit at a low corrosion period, and the length of the crack is equivalent to the width of the corrosion pit, about 0.047mm, and the crack propagates in a straight line. At high corrosion stage, cracks occur at multiple corrosion pits, and the crack propagation paths become tortuous, resulting in glyph cracks.