Photoelastic Stress Response of Complex 3D-Printed Particle Shapes

TL;DR

This paper explores the use of 3D printing combined with photoelastic analysis to visualize and measure stress within complex 3D-printed particles, including those with internal voids, advancing granular material research.

Contribution

It demonstrates the feasibility of using 3D printing and photoelasticity to analyze stress in complex 3D particles, including internal structures, which was previously challenging.

Findings

Layer orientation affects optical response but not mechanical properties.

Stress visualization is possible in complex 3D-printed particles.

Potential limitations and future directions are discussed.

Abstract

While stress visualization within 3-dimensional particles would greatly advance our understanding of the behaviors of complex particles, traditional photoelastic methods suffer from a lack of available technology for producing suitable complex particles. Recently, 3D-printing has created new possibilities for enhancing the scope of stress analysis within physically representative granules. Here, we investigate and evaluate opportunities offered by 3D-printing a single particle with a complex external shape with photoelastic properties. We report the results of X-ray computed tomography and 3D-printing, combined with traditional photoelastic analysis, to visualize strain for particles ranging from simple 2D discs to complex 3D printed coffee beans, including with internal voids. We find that the relative orientation of the print layers and the loading force affects the optical response of the discs, but without a significant difference in their mechanical properties. Furthermore, we present semi-quantitative measurements of stresses within 3D-printed complex particles. The paper outlines the potential limitations and areas of future interest for stress visualization of 3-dimensional particles.