Short fatigue crack growth in an aircraft Al-alloy of a 7075 type after shot peening

► Effect of shot peening on growth of short fatigue cracks in 7075 alloy was studied. ► Direct current potential drop method was adapted for short crack measurement. ► Short fatigue cracks of length 0.2-3 mm were prepared before shot peening. ► Especially short cracks were retarded by shot peening, threshold length was 0.35 mm. ► Retardation was attributed to compressive residual stresses, not to hardening.