Curvature-Based Quantification of Abrasion-Induced Shape Evolution in Stirred Crystallization

High Resolution Image Download MS PowerPoint Slide In stirred-cooling crystallization, frequent particle collisions during crystal growth are unavoidable and lead to mechanical abrasion. Abrasion reduces particle size while simultaneously smoothing edges and corners. Current descriptions of abrasion are expressed in terms of particle-size reduction or comparisons with idealized shapes, but neither can describe how crystal surfaces change locally during abrasion. To better describe surface changes during abrasion, we introduce a curvature-based shape descriptor roundness by aggregating local mean curvature over the particle surface using a continuous weighting function. The descriptor is benchmarked using simulated data and experimental μ-CT data obtained under elaborately designed stirred crystallization conditions. The results show that the descriptor captures abrasion-induced shape change even for irregular morphologies such as agglomerates and abrasion fragments.