| Autor: |
Haofeng Sun, Bingxiao Xu, Ruihan Li, Fuyun Liu, Chao Fu, Lianfeng Wei, Caiwang Tan |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Journal of Materials Research and Technology, Vol 29, Iss , Pp 4245-4255 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2238-7854 |
| DOI: |
10.1016/j.jmrt.2024.02.168 |
| Popis: |
Sub-atmospheric pressure environment and oscillation laser are both excellent ways to improve welded joint quality. However, the differences in their effects and mechanisms are unclear. Therefore, the differences between sub-atmospheric pressure and oscillating laser in weld formation, porosity suppression and grain size refinement were analyzed in this study. The results revealed that penetration depth of welded joint was increased to 6.09 mm under sub-atmospheric pressure environment while it was decreased to 3.3 mm under oscillation laser. Furthermore, reducing fluctuating vapor pressure and suppressing vortex formation were the main means to improve the keyhole stability and promote the escape of bubbles in a sub-atmospheric pressure environment. The improvement of the oscillating laser in these two aspects was attributed to enlarging keyhole area, shortening escape path and oscillation keyhole absorption. Additionally, the average grain size in the upper weld was reduced from 134.6 μm to 118.6 μm and 114.1 μm under the sub-atmospheric pressure environment and laser oscillation, respectively. The reduction of the temperature gradient led to former grain refinement while the increase of heterogeneous nucleation rate was responsible for latter grain refinement. Correspondingly, the mechanical properties of welded joints were improved. The study offered valuable insights for the application of laser welding with oscillation laser and sub-atmospheric pressure in industrial production. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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