Hydrogen micro pores in cast aluminum alloys

Hiroyuki Toda, Masakazu Kobayashi, Kentaro Uesugt, Yoshio Suzuki

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

According to our extensive 3-D non-destructive observations for various kinds of cast aluminum alloys, high-density micro pores have been identified to exist in all of the aluminum alloys except pure aluminum. The observation has been performed with the largest synchrotron radiation facility in the world, SPring-8. Growth/shrink and formation! annihilation behaviors of each micro pore are tracked during heat treatments and a plastic forming process. It has been clarified from the quantitative analysis of 3-D images that the micro pores exhibit the Ostwald ripening during the heat treatments. It has been found that considerable amount of hydrogen contained in the cast aluminum alloy is trapped in micro pores, while it is quite limited in a pure aluminum. Various efforts have been reported to eliminate such micro pores. Annihilation behaviors of micro pores under shot peening are demonstrated in 3-D. Since usually the porosity acts as fatigue crack initiation sites and fatal defects under tension, this information would be beneficial also from an industrial point of view. We also reports how mechanical properties of the cast aluminum are degraded due to the existence of micro pores in this review paper. Especially it is noteworthy that the ductile fracture of aluminum alloys is dominated by micro pore growth in addition to particle damage that is conventional text-book knowledge. Copyright

Original languageEnglish
Title of host publication69th World Foundry Congress 2010, WFC 2010
Pages49-53
Number of pages5
Publication statusPublished - Dec 1 2010
Externally publishedYes
Event69th World Foundry Congress 2010, WFC 2010 - Hangzhou, China
Duration: Oct 16 2010Oct 20 2010

Publication series

Name69th World Foundry Congress 2010, WFC 2010
Volume1

Other

Other69th World Foundry Congress 2010, WFC 2010
CountryChina
CityHangzhou
Period10/16/1010/20/10

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All Science Journal Classification (ASJC) codes

  • Surfaces, Coatings and Films

Cite this

Toda, H., Kobayashi, M., Uesugt, K., & Suzuki, Y. (2010). Hydrogen micro pores in cast aluminum alloys. In 69th World Foundry Congress 2010, WFC 2010 (pp. 49-53). (69th World Foundry Congress 2010, WFC 2010; Vol. 1).