Ali Hassan  Saleh Shatha, M. Rajaa  Abduljabbar, Adnan  Namaa Abood, Hassan  A. Abdulhadi, 
    Evaluation the Effect of Shot Peening Time on Static Torsional
Strength of AA7178-T6,
    Journal of Engineering and Applied Sciences,
    Volume 13,Issue 12,
    2018,
    Pages 4476-4481,
    ISSN 1816-949x,
    jeasci.2018.4476.4481,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2018.4476.4481)
    Abstract: In the current study, the effect of shot-peening on the static torsional strength of AA7178-T6 was
investigated. Time of shot-peening was adopted as a varied parameter to evaluate its effect on plastic state in
static torsion test of alloy. Residual stresses and surface roughness was measured to indicate the influence of
shot-peening time on alloy surface state. Torque predicted was calculated to evaluate the elastic torque and
plastic torque values according to shot-peening parameter. The results show that the shear strain decreases
whenever shot-peening time increase especially when up to 30 min that shear strain reduced by 45% and plastic
torque predicted also decreased at this time by 10% compare to its values of specimen without peened which
means that the strength of alloy improved with this process while shear stress decreased by 3.84% at this
condition. The total torque predicted was closed to experimental torque with average variation 14%.
Experimental torque decreased by 3.84% with the increasing of shot-peening time.
    Keywords: Torsion test;shot-peening;AA7178-T6;plastic torque;elastic torque;torque predicted