WEB In-situ Shock Stress Field Detection using Laser Array Raman SpectroscopyWednesday (01.01.2020) 01:45 - 02:00 Part of:
Time-gated Raman spectroscopy has been used in the past for chemical analysis at a nanosecond time scale. Based on prior calibration, the Raman spectra can be used to predict local stress on a microscale spot size. In this work, we used a unique setup where multi-spot Raman spectra were obtained over a microstructure using laser array spots on the sample. The excited Raman signal from each spot on the array was collected into a two-dimensional array of optical fibers for simultaneous spectrum analysis by a spectrograph. This technique was used to measure shock wave propagation through at the interface between octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and Hydroxyl-terminated polybutadiene (HTPB) binder at strain rates higher than 1e6/s. The study shows the effects of interface chemistry on stress propagation through the interface.