Characterisation of 3D strain heterogeneity at the microstructure scale during Low Cycle Fatigue of an AlSi7Cu3Mg alloy at 250°C

•Low cycle fatigue damage of AlSi7Cu3 at 250 °C is studied with X-ray tomography.•High resolution 3D strain fields were measured with Digital Volume Correlation.•Cracks initiate at pores and propagate through hard particles nearby.•The cumulative von Mises strain was measured within particles before their failure.•The failure strain ranks as: eutectic Si < Fe intermetallics < Cu intermetallics.