Effect of Proximity and Dimension of Two Artificial Pitting Holes on the Fatigue Endurance of Aluminum Alloy AISI 6061-T6 Under Rotating Bending Fatigue Tests

This work deals with the study of the two artificial pitting holes effects, caused by their dimensions and proximity, on the fatigue endurance of aluminum alloy AISI 6061-T6 under rotating bending fatigue tests. Stress concentration induced by artificial pitting holes is analyzed and correlated with the experimental fatigue life. It is found that the stress concentration increases exponentially when the two pitting holes approach, and this induces an important reduction in the fatigue life. Concerning the diameter variation of one pitting in regard to the second, no important influence was observed on fatigue life for a given separation between them; this implies that the separation between the two artificial pitting holes and the associated stress concentration is the principal parameter on the fatigue life under these conditions. Finally, results are discussed and conclusions are presented involving the fatigue life, proximity, and dimension of pitting holes, stress concentration factor, and fracture surfaces where the failure origin is identified.