High-temperature DIC based on aluminium dihydrogen phosphate speckle

Digital image correlation (DIC) method has been widely used for measurement in high temperature environment, where speckle pattern that can withstand high temperature and maintain good stability is required. In this work we develop a simple method to fabricate speckle pattern for high temperature application. The curing temperature of the speckle is controlled under 350 °C to avoid potential damage to the substrate material. The speckle can resist temperature up to 1050 °C for minimum 0.5 h. Three point bending experiment was carried out at 700 °C to test the speckle. Results show that this high temperature speckle exhibits excellent adhesion to the substrate. This non-invasive speckle shows great potential for improving the measurement reliability at high temperature in engineering application.