Experimental and numerical investigation of material heterogeneity in shot peened aluminium alloy AA2024-T351

► The effects of shot peening on aluminium alloy AA2024-T351 were investigated. ► Experimental and numerical methods were combined to assess the material state. ► Residual stress, work hardening state, topography and microstructure were studied. ► The random impact sequence altered the heterogeneity at various length scales. ► The proposed approach could lead to improved fatigue life prediction models.