Shot peening was carried out on an 6061-T652 aluminium alloy, the effe
cts of two main peening parameters, the air blast pressure and the exp
osure time, on the depth of yield and the maximum residual stress indu
ced in the shot peened specimens, being measured. For the residual str
ess, the traditional strain-gauge hole-drilling method and a laser hol
ographic interferometry technique were used. Analysis of the experimen
tal data showed that the residual stress is affected by the air-blast
pressure to a power law, and that there is an exponential relationship
between the maximum induced stress and the exposure time, an empirica
l equation for the relationship of the maximum stress with the pressur
e and time being thus obtained. A similar expression was arrived at al
so for the variation of the depth of the yield zone with pressure and
time.