Time-resolved ex situ Raman/FT-IR spectroscopic study of structural changes in polymeric gears during operation: Towards the development of operando spectroscopic systems for polymer gears. (September 2022)

• Record Type: Journal Article
• Authors: Okubo, H.; Kobayashi, K.; Iba, D.; Moriwaki, I.; Yao, S.; Sasaki, S.
• Is Part Of: Polymer testing. Volume 113(2022)
• Publication Date: 2022-09
• Subjects: Polymeric gears -- Wear -- Ex situ -- Raman -- FT-IR; Polymers -- Testing -- Periodicals; Polymères -- Tests -- Périodiques; 620.1920287
• DOI: 10.1016/j.polymertesting.2022.107675
• Languages: English
• ISSNs: 0142-9418

Abstract

Abstract: In this study, time-resolved ex situ Raman and Fourier transform infrared (FT-IR) spectroscopy were performed to monitor structural changes in a polyamide (PA) 66 gear during operation and reveal the failure mechanisms of the material. A gear test was performed using a lab-built gear tester, which is a power-absorption type. Raman and FT-IR analyses were performed on the side gear surfaces around the root of the gear (at the side of the active flank), where a bending stress is continuously loaded during operation. The results showed that the crystallinity changed, amide related bonds were broken, trans -gauche (TG) transformation occurred, and a change in the inner stress condition of the PA66 gear occurred over time. It was concluded that these changes interact with each other during operation and are related to the failure of the PA66 gear, such as the initiation of the plastic gear degradation. Highlights: Time-resolved Raman and FT-IR spectroscopic analyses performed on PA66 gears. FT-IR indicated: amorphization, amide bonds broken, and TG transformation of PA66. Raman indicated: peaks shifts for CO, N–H, C–C, and C–CO after 60, 000 cycles. Internal structural changes during operation related to gear failure.