Improved monochromatic pyrometry for synchronous measurement of full-field temperature and deformation

Measuring the temperature and deformation synchronously at elevated temperatures is technically challenging and has become a major concern in the evaluation of mechanical properties. In this study, a simple, easy-to-implement, yet effective monochromatic pyrometry is established for non-contact and full-field temperature measurements, which can significantly reduce the error caused by the camera's channel crosstalk that commonly occurs in the existing improved two-color method. In addition, high-temperature digital image correlation, combined with band-pass filtering and monochromatic illumination, is applied for deformation measurement. Subsequently, an experimental system was set up to validate the accuracy of the proposed method, which consists of a CCD camera for image capturing, a blue bandpass filter for radiation suppression, blue light irradiation for light compensation, and an infrared pyrometer for temperature recording. The results of the thermal heating experiment on the C/SiC sample proved that the selection of camera channel R in monochromatic pyrometry can reduce the error by channel crosstalk, and the proposed method is applicable for synchronous measurement of temperature and deformation.