Communication: n-Radii Method to Quantify Multiscale Topology of Particles Used in Metal Casting Processes

Expendable molds, such as sand, investment, and shell molds, are made from different types of refractory particles bonded by binders. Multiscale characterization of particle macro-shape and micro-surface topology is critical for achieving the required combination of competing technological properties, such as strength, mold shape stability, and gas permeability. However, common methods that accurately quantify macro-shape have several drawbacks, often resulting in the underestimation of sharp corners and surface texture. In this communication, the n- radii method previously suggested for the quantification of graphite shape in cast iron 1 was applied to assess the shape of refractory particles used in metal casting processes. The suggested method is based on plotting n -radii from the particle’s center of mass to its perimeter while computing multiscale topological characteristics from the obtained dataset. Images of different industrial molding media were used to verify the ability of the method to numerically describe and classify different particle shape classes. The suggested approach could be useful for material quality control and the optimization of molding processes.