Surface layer properties and fatigue behavior in Al 7075‐T73 and Ti‐6Al‐4V: Comparing results after laser peening; shot peening and ball‐burnishing

Abstract

Purpose

The purpose of this paper is to investigate the influence of mechanical surface treatments on the surface layer properties and the fatigue performance of the aircraft alloys Al 7075‐T73 and Ti‐6Al‐4V

Design/methodology/approach

Laser peening without coating (LPwC), shot peening (SP), ultrasonic shot peening (USP) and ball burnishing (BB) were applied and the resulting changes in surface roughness and residual stress‐depth profiles were evaluated. Fatigue performance of both alloys was tested in rotating beam loading (R=−1) on hourglass‐shaped specimens and the results were compared with the electrolytically polished (EP) reference conditions.

Findings

All studied mechanical surface treatments led to pronounced increases in fully reversed fatigue lives and fatigue strengths in both Al 7075‐T73 and Ti‐6Al‐4V.

Originality/value

To the authors' knowledge, this is the first paper that compares fatigue performance of a wide variety of mechanically surface treated conditions in two aircraft alloys.

Citation

Wagner, L., Mhaede, M., Wollmann, M., Altenberger, I. and Sano, Y. (2011), "Surface layer properties and fatigue behavior in Al 7075‐T73 and Ti‐6Al‐4V: Comparing results after laser peening; shot peening and ball‐burnishing", International Journal of Structural Integrity, Vol. 2 No. 2, pp. 185-199. https://doi.org/10.1108/17579861111135923