关键词: 高温, 数字图像相关方法, 热变形, 热膨胀系数, 非接触测量

Abstract: A novel non-contact high-temperature thermal deformation measuring system that combines a transient aerodynamic heating simulation device and the digital image correlation (DIC) technique is proposed for the high-temperature thermal deformation measurement of structural materials used in high-speed vehicles. A test sample can be heated rapidly and accurately from room temperature up to 1 200 ℃ using the infrared radiator of the transient aerodynamic heating simulation device, and the digital images of the test sample surface at various temperatures are recorded and subsequently analyzed by DIC technique to extract full-filed thermal deformation. To validate the performance of the system, the full-field thermal deformation and coefficients of thermal expansion of a chromiumnickel austenite stainless steel sample at the temperature range of 20-550 ℃ is measured. The results indicate that the proposed system can be used easily and quickly for the accurate full-field high-temperature thermal deformation measurement of aerospace materials.

Key words: high-temperature, digital image correlation technique, thermal deformation, coefficient of thermal expansion, non-contact measure