Fatigue Behavior of A356 Cast Aluminum Alloy Microstructurally Modified by Friction Stir Processing under Low Strain Rate Condition

Abstract:

The fatigue behavior of cast aluminum alloy, A356-T6, microstructurally modified by the friction stir processing (FSP) was investigated. The FSP conditions were set to be the tool rotational speed of 500 rpm and traveling speed of 200 mm/min, in which the strain rate was relatively low. Plane bending fatigue tests have been performed using the as-cast and friction stir processed (FSPed) specimens. Fatigue strengths in the finite life region and the fatigue limit of the FSPed specimens were highly improved compared with the as-cast ones resulting from the elimination of casting defects by the FSP. However, the crack growth rates of the FSPed specimens were faster than those of the as-cast ones due to the softening of the material by heat input during the FSP. The effects of FSP with low stain rate were discussed based on the microstructural consideration.

• Periodical: Key Engineering Materials (Volumes 525-526)
• Pages: 169-172
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.525-526.169
• Online since: November 2012
• Authors: Toshifumi Kakiuchi, Yoshihiko Uematsu, Yasunari Tozaki
• Keywords: Cast Aluminum Alloy, Fatigue Behavior, Friction Stir Processing (FSP), Microstructural Modification

References

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