Ultrasonic embedding of nickel-coated fiber Bragg grating in aluminum and associated sensing characteristics

Solid-state additive manufacturing for metallized optical fiber integration

“…The effect of this increase is to place further stress directly onto the coating material, and as it is stripped from the central silica fiber, deposit it further from the circumference of the fastened silica core. These results differ substantially from results obtained by Li et al in their work in the embedding of nickel coated optical fibers through ultrasonic spot welding [19]. Their work demonstrated that in the case of static spot welding, the nickel coating remained directly attached not only to the circumference of the fiber, but it also retained its original shape.…”

“…Li and co-workers recently reported the application of Nickel coatings to optical fibers as a means of improving the durability of Fiber Bragg Gratings (FBG's) encapsulated through Ultrasonic Spot Welding (USW) [19]. Ultrasonic Spot Welding (USW) is a welding technique capable of joining non-ferrous similar and dissimilar metal components, at small localized points, through the use of high frequency sound energy to soften or melt the material under an applied pressure.…”

An Electroplating Method for Surface Mounting Optical Fiber Sensors on the Metal Substrate

“…In addition, although many methods for embedding FBG sensors into metal structures or on the surface of metal substrates are well developed, there are still a few aspects that are problematic. Examples include, the structural stability and the optimum temperature scope of FBG sensors are reduced because of the use of organic adhesive [3]; the response rate to temperature and strain of FBG bonded by elastomer-modified epoxy vinyl ester resin is reduced evidently [8]; the spectrum of the FBG changes a lot when it is embedded in the metal by brazing owing to the compressive stress during cooling process [2], [9]; the metal coated FBG would be destroyed during ultrasonic welding process due to the combined action of pressure, vibration and friction [10]. In contrast, electroplating is a potential method for positioning FBG due to the prominent advantages of low residual stress after electroplating [11], good mechanical properties [12] and large optimum temperature scope of FBG sensors.…”

In-situ strain sensing with fiber optic sensors embedded into stainless steel 316

“…These metal jackets are typically applied by low temperature processes such as electroless plating [9] or a mixture of electro-plating and magnetron sputtering [10]. Subsequently, the jacketed fibers are encapsulated either by using low temperature manufacturing processes such as ultrasonic consolidation [11] or by using brazing [12] and high temperature additive manufacturing processes such as fused deposition modelling [10]. Low temperature embedding processes inherently limit the range of applications that the final component may be used in and the high temperature approach described by Li [10] requires very thick nickel fiber jackets which significantly change the final component mechanical and material properties.…”