臺灣博碩士論文加值系統

在這項研究中，兩個金屬塗層光纖布拉格光柵（MCFBG）感測器和一個裸FBG感測器嵌入到複合材料其纖維的貼合角度為0-90度和0-45-90度的複合材料中，以監測固化過程中材料的性質變化。此後，使用嵌入的金屬塗覆的裸FBG通過監測光譜變化來計算複合材料的殘餘固化應變，並在纖維的貼合角度為0-90度和0-45-90度的複合材料之間的各種層壓位置進行殘餘應變比較。這是尚未研究過的研究課題。
金屬塗層和裸FBG感測器的光譜在固化過程中移動並變形。這種現像是由複材固化過程中的殘餘應變引起的。根據實驗結果，與嵌人裸露FBG感測器於纖維的貼合角度為0-45-90度的複合材料相比，具有ZrN塗層感測器的貼合角度為0-45-90℃的複合材料，其殘餘軸向應變減少了2.742％，而具有CrN塗層感測器的纖維的貼合角度為0-90度的層壓層減少了3.624％。 與具有裸露FBG感測器的纖維貼合角度為0-45-90度的複合材料相比，具有ZrN塗層感測器的纖維的貼合角度為0-90度的層壓層的殘餘軸向應變減少了7.553％。具有CrN塗層的感測器的纖維貼合角度為0-45-90度的複合材料層壓層減少了8.025％。因此，纖維貼合角度為0-45-90度的複合材料的軸向殘餘應變減小比纖維貼合角度為0-90度的層壓層更明顯。
我還發現，沒有金屬塗層的裸FBG感測器比具有金屬塗層的MCFBG感測器具有更大的曲率。MCFBG感測器上的金屬塗層具有良好的保護作用，可延長感測器的使用壽命。總之，本研究已經證明了塗有氮化物薄膜的FBG感測器的有效性能。
接下來的研究提出了一種小型U形彎曲感應干涉光纖感測器；這種新型感測器是使用機械裝置，熱源，光纖和封裝模塊製造的探針型感測器。該探針型感測器克服了傳統光纖的缺點，包括難以修復和受外力影響的趨勢。我製造了三種具有不同曲率半徑的感測器。具體而言，使用具有三個半徑（1.5mm，2.0mm和3.0mm）的感測器來測量濃度為6％至30％的普通水和葡萄糖溶液（濃度之間的間隔為4％）。結果表明，最大靈敏度為0.85 dB /％，線性相關係數為0.925。結果進一步表明，小型U形彎曲干涉光纖感測器不僅可以在葡萄糖溶液的測量中實現高靈敏度，而且還可以實現很高的穩定性和可重複性。
關於嵌入具有不同直徑蝕刻的四根光纖布拉格光柵的複合材料的應變。我發現FBG的直徑越小，其波長飄移的變化越大。四根FBG的波長偏移在30度至70度的溫度範圍內開始呈現非線性趨勢。其中一根FBG (AN1)在超過70度時仍然不穩定。其他三根FBG較為穩定。所有FBG的波長位置比複合材料成化前的光譜的波長位置更偏向於更短的波長方向。

In this study, two metal-coated fiber Bragg grating (MCFBG) sensors and one bare FBG sensor were embedded into a cross-ply and a quasi-isotropic-ply laminated composite material to monitor the property changes of the material during the curing process. Thereafter, the embedded metal-coated and bare FBG were used to calculate the residual curing strain of the composite by monitoring the spectrum variations and to make residual strain comparisons in the various laminated locations between cross-ply laminates and quasi-isotropic-ply laminates. This is a subject of research that has not yet been investigated.
The spectra of the metal-coated and bare FBG sensors shift and become deformed during the curing process. This phenomenon is caused by residual strain during composite curing. According to the experimental results, the residual axial strain of the cross-ply laminate-layer with a ZrN-coated sensor was reduced by 2.742% compared to that of the cross-ply laminate-layer with a bare FBG sensor, while that of the cross-ply laminate-layer with a CrN-coated sensor was reduced by 3.624%. The residual axial strain of the quasi-isotropic-ply laminate-layer with a ZrN-coated sensor was reduced by 7.553% compared to that of the quasi-isotropic-ply laminate-layer with the bare FBG sensor, while that of the quasi-isotropic-ply laminate-layer with a CrN-coated sensor was reduced by 8.025%.Therefore, the reduced axial residual strain is more pronounced in the quasi-isotropic-ply laminates than in the cross-ply laminates.
We also found that the bare FBG sensors without a metal coating have a greater degree of curvature than the MCFBG sensors, which have a metal coating. The metal coating on the MCFBG sensor has a good protective effect that can extend the service life of the sensor. In summary, the effective performance of an FBG sensor coated with nitride thin films has been demonstrated in this study.
The next study proposes a small U-shaped bending-induced interference optical fiber sensor; this novel sensor is a probe-type sensor manufactured using a mechanical device, a heat source, optical fiber and a packaging module. This probe-type sensor overcomes the shortcomings of conventional optical fibers, including being difficult to repair and a tendency to be influenced by external forces. We manufactured three types of sensors with different curvature radiuses. Specifically, sensors with three radiuses (1.5 mm, 2.0 mm, and 3.0 mm) were used to measure common water and glucose solutions with concentrations of between 6% and 30% (the interval between concentrations was 4%). The results show that the maximal sensitivity was 0.85 dB/% and that the linearly-dependent coefficient was 0.925. The results further show that not only can the small U-shaped bending-induced interference optical fiber sensor achieve high sensitivity in the measurement of glucose solutions, but that it can also achieve great stability and repeatability.
About the strain of composite four fiber Bragg grating with etched different diameters. I found that the smaller the diameter of the FBG, the bigger its wavelength shifts. The wavelength shift of the four FBGs begins to exhibit a non-linear appearance over a temperature range of 30°C to 70°C. The FBG AN1 is still unstable at over 70°C. The other FBGs are stable. The wavelength position of all FBGs is more skewed to the shorter wavelength direction than the wavelength position of the spectrum before the formation.

Acknowledgements vi
TABLE OF CONTENTS vii
LIST OF TABLE x
LIST OF FIGURES xi
SYMBOLS xvii
ChapterⅠ: Introduction 1
1-1 Epoxy resin substrate 1
1-2 Carbon fiber reinforced materials 1
1-3 Motivation for the MCFBG embedded into laminated composite material 2
1-4 Motivation for the U-shaped optical fiber sensor to measure water and glucose solutions 5
1-5 Literature Review about the MCFBG embedded into laminated composite material 6
1-6 Literature review about U-shaped optical fiber sensor to measure water and glucose solutions 16
1-7 Literature review about etched Fiber Bragg grating (FBG) 24
This dissertation is divided into 6 chapters: 31
ChapterⅡ: Fundamental theory of FBG and WGM sensors 34
2-1 Materials for the sensors 34
2-2 Working principle of FBG sensors 34
2-2.1 Basic principle of fiber grating 34
2-2.2 Photoelastic theory 36
2-2.3 Bragg fiber grating theory 39
2-2.4 Relationship between wavelength shift of Bragg fiber grating and temperature change 41
2-2.5 Relationship between wavelength shift and axial strain of Bragg fiber grating 42
2-2.6 Relationship between wavelength shift of Bragg fiber grating and axial and lateral strain 44
2-3 The strain sensitivity of the FBG with nitride film sensor 48
2-4 Working principle of U-shaped optical fiber sensors 49
2-4.1 Basic theory of the WGM 49
2-4.2 Phase difference caused by fiber bending 51
ChapterⅢ: Research Method and Procedures 56
3-1 The MCFBG sensor sputtering process and fabrication 56
3-2 Experiment set-up for the embedding of the MCFBG and bare sensors and curing monitoring 56
3-3 Experiment for the process of the embedding of the MCFBG and bare sensors and curing monitoring 58
3-4 Experiment set-up for the process of small U-shaped bending-induced interference glucose concentration sensor 59
3-5 Experiment for the process of small U-shaped bending-induced interference glucose concentration sensor 60
3-6 Experiment for the process of etching the Fiber Bragg grating (FBG) 62
Chapter Ⅳ: Results and discussion 66
4-1 The MCFBG sensor 66
4-2 The U-shaped optical fiber sensor 76
4-2.1 Concentration Refractive Index Measurement of Solutions to be measured 76
4-2.2 Concentration Test of Water/Glucose Solution 77
4-3 The optical fiber with etched different diameters embedded into composite 83
Chapter Ｖ: Conclusions 87
5-1 Conclusions of the MCFBG embedded into composite material 87
5-2 Conclusions of the U-shaped sensor to measure water and glucose solutions 88
5-3 Conclusions of the strain of composite fiber Bragg grating with etched different diameters 89
Chapter Ⅵ: Future work 90
Reference 91
Appendixes 99

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