Improvement on the Fatigue Performance of 2024-T4 Alloy by Synergistic Coating Technology

Materials

Xi-Shu Wang²  Xing-Wu Guo¹  Xu-Dong Li² 

[1] National Engineering Research Center for Light Alloy Net Forming, School of Material Science & Engineering, Shanghai Jiao Tong University, Shanghai 200030, China; E-Mail:;Department of Engineering Mechanics, Key Laboratory of Applied Mechanics, Tsinghua University, Beijing 100084, China; E-Mails:

关键词: plasma electrolytic oxidation;    hard anodized;    fatigue performance;    synergistic coating;    aluminum alloy;   

DOI  :  10.3390/ma7053533

来源: mdpi

【 摘 要 】

In this paper, rotating bending fatigue tests of 2024-T4 Al alloy with different oxide coatings were carried out. Compared to the uncoated and previously reported oxide coatings of aluminum alloys, the fatigue strength is able to be enhanced by using a novel oxide coating with sealing pore technology. These results indicate that the better the coating surface quality is, the more excellent the fatigue performance under rotating bending fatigue loading is. The improvement on the fatigue performance is mainly because the fatigue crack initiation and the early stage of fatigue crack growth at the coating layer can be delayed after PEO coating with pore sealing. Therefore, it is a so-called synergistic coating technology for various uses, including welding thermal cracks and filling micro-pores. The effects of different oxide coatings on surface hardness, compressive residual stress, morphology and fatigue fracture morphology are discussed. A critical compressive residual stress of about 95–100 MPa is proposed.

【 授权许可】

CC BY   
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