Optical Fiber Sensor for Strain Monitoring of Metallic Device Produced by Very High-Power Ultrasonic Additive Manufacturing

Abstract

Embedding of optical fiber sensors into materials to detect and monitor the deformation and damage of structures has attracted much attention recently. However, the embedding of optical fiber sensors into metallic materials is usually difficult due to lack of suitable technique, which does not damage the optical fiber during metal processing. In this paper, we introduced a very high-power ultrasonic additive manufacturing (UAM) for producing metallic structure optical fiber sensors. Single-mode optical fibers (SMFs) were successfully embedded in aluminum (Al 1100) matrix by this technique. Tensile strain experiments were performed by a fiber optical white-light interferometric sensing system, and the effect of consolidation contact pressure of UAM on the output strain-applied strain relation was examined systematically. As the appropriate contact pressure of 1300-1350 N was taken, and the excellent and reliable out strain-applied strain relations were obtained. These results demonstrate that the UAM produced optical sensor like a “nervous system” is capable of monitoring the health condition of metallic structural device.