Text
Fracture toughness is hard to quantify via nanoindentation or FIB-prepared micro-specimen testing. We used micro-scratch testing with acoustic emission to rapidly obtain statistically relevant results across scales (1–100 μm), capturing hydration products and cement paste properties. Acoustic emission identified portlandite cracking, aiding phase separation. Accurate fracture toughness estimates are crucial for calibrating multi-scale models to predict macro-scale properties for structural design.
Description
a) SEM-BSE image of a scratch line made with a spherical tip of 10 μm radius, b) mean fracture toughness of individual phases along the scratch distance, measured with a maximum vertical force of 25 mN, c) acoustic emission signal record.