Fracture Strength Evaluation of Agglomerates of Fatty Acid-Coated CaCO₃ Nanoparticles by Nano-Indentation

Abstract

Nanoparticles often form agglomerates during their manufacturing process. When nanoparticles form agglomerates, their inherent properties cannot be fully exploited. In this study, we attempted to establish a conventional method to evaluate the fracture strength of agglomerates into smaller parts. We used a commercially available nano-indentation instrument with a flat indenter tip. We chose calcium carbonate nanoparticles with stearic acid coatings as model materials. It was found that the more fatty acid that is coated on the particle surface, the stronger the agglomerates become. The technique we propose in this study can be used to rapidly evaluate the fracture strength of nanoparticle agglomerates.

Keywords

• calcium carbonate
• nanomaterials
• surface treatment
• micromechanical properties
• fracture toughness