| Autor: |
Lan-bo Ma, Wen-jin Cheng, Xin-li Guo, Bing-zheng Fan, Yang Guan, Yi-peng Li, Lei Jin, Guo-yan Shui, Yi-zhong Jiang, Xun Sun |
| Předmět: |
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| Zdroj: |
China Foundry; Nov2024, Vol. 21 Issue 6, p702-708, 7p |
| Abstrakt: |
Non-metallic inclusions and zyglo indications frequently occur in the superalloy castings produced through the traditional vacuum gravity investment casting process, particularly in components with thin-walled and complex structural features. The vacuum-assisted low-pressure casting (VLC), a type of counter-gravity casting (CGC) method, has been developed to minimize non-metallic inclusions and zyglo indications in superalloy castings. Rectifying frames for gas turbines made from K446 alloy were produced semi-continuously using the VLC process and subsequently evaluated through tensile testing, chemical composition analysis, X-ray diffraction, and zyglo penetrant inspection. The results indicate a roughly 10% improvement in tensile strength at 800 ℃ compared to gravity casting. Moreover, no significant changes are observed in the chemical composition of the alloys from the beginning to the end of a casting campaign, indicating that the developed VLC process is viable for the engineering-scale production of superalloy castings. Compared to traditional vacuum gravity casting (GC) method, the application of VLC can reduce the numbers of non-metallic inclusions and Zyglo indications in the castings by over 80%. At the same time, it significantly shortens the production time by 3 to 5 days. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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