Terahertz time-domain spectroscopy system-based stress measurement method

• Main Authors: WANG ZHIYONG, SONG WEI, LI LIN'AN, ZHANG XU, WANG SHIBIN
• Format: Patent
• Language: English
• Published: 29.04.2015
• Subjects: MEASURING; MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER,MECHANICAL EFFICIENCY, OR FLUID PRESSURE; PHYSICS; TESTING

The invention discloses a terahertz time-domain spectroscopy system-based stress measurement method. The method comprises the following steps: placing an experimental piece and loading equipment into a constructed terahertz spectroscopy system together; generating a terahertz pulse by utilizing a femtosecond laser, and receiving a signal by utilizing a terahertz detecting device; acquiring phase frequency curves under an unloaded working condition and a loaded working condition; performing subtraction on the two phase frequency curves to obtain a terahertz wave phase difference value caused by external stress; reversely deducing a stress component of an loaded experimental piece by utilizing the change of a terahertz wave phase; optimizing the stress component of the experimental piece through a target function, and acquiring a final stress result. A transparent material can be measured by the method, and a non-transparent material can also be measured by the method without manufacturing an experimental model. According to the method, an improved terahertz time-domain spectroscopy system is utilized; the internal stress information of a loaded piece is obtained by analyzing the phase change of a terahertz wave; a new experiment means is provided for detecting the internal stress of an object.