Influence Of Different Peening Media On Stress Corr.and Corr.fatigue Behav.of A Welded A1znmg Alloy

Author:  Koehler, W.
Source:  Adv. in Surf. Treat.Tech.Vol.3,221-227 (Pergamon)
Doc ID:  1986047
Year of Publication:  1986
Abstract:  
Using the alloy A1Zn4.5Mg2 as an example, the influence of shot peening on the stress corrosion resistance and corrosion fatigue behavior was investigated. Welded tensile test samples of alloy were shot peened with glass, steel and ceramic beads as well as granulated aluminium material. The samples were tested in 2% and 3.5% NaC1-solution for stress corrosion resistance. With glass, steel and Granal, a significant improvement of life over 60 days without fracture was achieved in these tests. Furthermore, a significant improvement of the corrosion fatigue behavior in 2% NaC1 was achieved. For better understanding of the mechanism involved, the residual compressive stresses were measured by X-ray methods. The individual results of the stress and fatigue corrosion tests and the effect of peening are discussed. Descriptors: Welded joints-- Corrosion; Aluminum base alloys-- Corrosion; Zinc-- Alloying elements; Magnesium-- Alloying elements; Stress corrosion-- Stress effects; Corrosion fatigue-- Stress effects; Sodium chloride-- Environment; Residual stress; Shot peening