The effect of manufacturing defects on the fatigue life of selective laser melted Ti-6Al-4V structures
| Autor: | Shengchuan Wu, Yanan Hu, Philip J. Withers, Guozheng Kang, J. Zhang, H.Y.X. Bao, Y.N. Fu |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Fatigue crack initiation and growth Additive manufacturing Population 02 engineering and technology 010402 general chemistry 01 natural sciences law.invention High cycle fatigue (HCF) law lcsh:TA401-492 General Materials Science Composite material Selective laser melting education Porosity Defect tolerance method education.field_of_study Fusion Mechanical Engineering Radius Paris' law 021001 nanoscience & nanotechnology Laser Fatigue limit 0104 chemical sciences Mechanics of Materials lcsh:Materials of engineering and construction. Mechanics of materials 0210 nano-technology Digital printing |
| Zdroj: | Materials & Design Materials & Design, Vol 192, Iss, Pp 108708-(2020) |
| ISSN: | 0264-1275 |
| DOI: | 10.1016/j.matdes.2020.108708 |
| Popis: | The manufacturing defects introduced by selective laser melting typically lead to lower fatigue strength and a larger variation in fatigue life compared to conventionally manufactured structures. X-ray micro computed tomography (μCT) is used to characterize the porosity and lack of fusion defects in terms of population, morphology, dimension and location. The defect size and location are combined with the NASA/FLACGRO (NASGRO) fatigue crack growth model to predict the likely fatigue life, in which an effective initial crack length is defined using the cyclic plastic zone and the defect radius. An eXtended defect zone (XDZ) describing the propensity for local plasticity during fatigue around a defect has been shown through numerical analysis to be a good indicator of the ranking of the threat to fatigue caused by differently located manufacturing defects. This indicates that the effect of a defect, initial radius, r0, is likely to be pronounced when its center is within 2r0 of the surface and maximal when it lies just beneath the surface. |
| Databáze: | OpenAIRE |
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