3D strain measurement using Tomo-PIV with an interrogation voxel size of 40 × 40 × 40 voxels for a specimen with a particle density of 0.014 ppp at each cross section.

<p>(a) Distributions of the correlation values between the first two successive 3D images and the normal strain. (b) Correlation value between the first two successive 3D images. (c) Normal strain. (d) Maximum measurement error of the normal strain.