Shot-Peening Sensitivity of Aerospace Materials

Abstract

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Characterization of the microstructure, mechanical properties, and shot peening response of an industrially processed Al–Zn–Mg–Cu PM alloy

“…Both Benedetti et al (2009) and Wagner et al (2011) saw gains in fatigue strength of approximately 50% with select peening parameters. However, others including Honda et al (2005) and Grendahl et al (2007) saw little to no improvements in the fatigue strength of AA7075 by peening, while Oguri (2011) saw no gains from conventional shot peening, but slight improvements with a fine particle shot peening process. Although there have been varying results describing the effectiveness of shot peening as a means to extend the fatigue life of AA7075, it is clear that with proper peening parameters, appreciable gains can be realized by shot peening aluminum alloys.…”

Enhancing surface layer properties of an aircraft aluminum alloy by shot peening using response surface methodology

“…They verified that shot peening is an effective way of improving the compressive residual stress and microstructure of the austenitic stainless steel. The compressive residual stress of shot-peened aluminum alloy was studied by Sharp and Clark [11], Grendahl et al [12], Luong and Hill [13], and Gao [14]. Sharp and Clark [11] demonstrated that shot peening extends the fatigue life of 7050 aluminum alloy and the residual stress increases up to approximately half the yield stress.…”

“…Sharp and Clark [11] demonstrated that shot peening extends the fatigue life of 7050 aluminum alloy and the residual stress increases up to approximately half the yield stress. Grendahl et al [12] studied the residual stress and surface roughness for various types of titanium, steel, and aluminum alloy specimens. They reported that shot peening increases compressive residual stress and that surface roughness becomes greater as the shot peening intensity increases.…”

Fatigue life enhancement of aluminum alloy for aircraft by Fine Particle Shot Peening (FPSP)

“…The surface was polished to avoid influence of machined scar. The Kt = 1 where the effect of shot peening is not remarkable in case of convention SP as Grendahl et al (2007) have reported for machined 7075-T73. Flat plate specimens made of 7075-T6 are used for residual stress measurement.…”

“…Marsh (1993) has described the importance of shot peening effect on fatigue performances for several metallic materials in various industries including aerospace. Recently, Grendahl et al (2007) have reported the effect of shot peening on aerospace materials, including aluminum titanium and steel. They revealed the detailed effect of shot peening on aluminum alloy, however, the effects by several shot peening conditions on fatigue life enhancement are limited especially for Kt = 1 specimens.…”