High-temperature thermal disturbance elimination method based on multi-channel extraction and correction.

Area of Science:

• Materials Science
• Optical Engineering
• Metrology

Background:

• High-temperature Digital Image Correlation (DIC) is crucial for material analysis.
• Thermal disturbance significantly compromises DIC measurement accuracy in high-temperature environments.
• Existing methods struggle to effectively mitigate thermal interference.

Purpose of the Study:

• To develop a cost-effective method for eliminating thermal disturbance errors in high-temperature DIC.
• To enhance the accuracy and reliability of DIC measurements under thermal stress.
• To propose a novel multi-channel separation technique for thermal error correction.

Main Methods:

• A multi-channel separation technique combined with a low-cost laser speckle device was employed.
• A blue laser speckle generation system was designed and projected onto a blue background.
• A color camera captured images under green LED illumination, followed by channel separation and displacement calculation.
• Subtraction of displacement fields from different channels isolated and corrected thermal disturbance errors.

Main Results:

• The proposed method successfully separated and corrected thermal disturbance errors in high-temperature DIC measurements.
• Experimental verification at room and high temperatures demonstrated high consistency between corrected and true displacement values.
• The reliability of the multi-channel separation technique for accurate high-temperature DIC was confirmed.

Conclusions:

• The developed laser speckle-based multi-channel separation technique effectively eliminates thermal disturbance errors in high-temperature DIC.
• This method offers a reliable and accurate solution for high-temperature metrology applications.
• The findings pave the way for more precise material characterization in extreme thermal conditions.