以雷射超音波技術建立高溫材料性質量測平台及其應用

Development and application of a high temperature material characterization platform based on laser ultrasound technique

葉承鴻(Cheng-Hung Yeh)

指導教授 ： 楊哲化

國立臺北科技大學/機電學院/機電科技研究所/博士(2012年)

摘要

多數的材料性質量測技術適用於常溫環境而在高溫環境的應用上有其困難性。然而，結構材料常因工作環境處於高溫的狀態下而導致材料性質的變化或劣化；材料也常因不可避免的高溫製程再冷卻所導致的高殘餘應力而對後續的應用產生困擾。因此，開發適用於高溫環境下的材料性質量測或監測技術是材料製造及應用上的一大課題。本研究以雷射超音波技術作為量測基礎測得沿待測物傳播之多種導波頻散關係，並結合導波理論模型以及全域最佳化的洗牌複合演進演算法，建立一個適用於高溫環境中的材料機械性質量測平台。本平台具備了非接觸、非破壞、遠距操作等各項量測優點，軟體介面具整合性以及擴充性可於單一平台內反算各種幾何外型之材料參數並可擴充導波理論模型，目前可量測平板、圓管以及膜層的等向性材料性質。另外本研究利用所開發的平台量測未氫化、200ppm以及500ppm含氫量之鋯管和不同製程條件的熔射鎳鋁合金膜層在常溫至295oC溫度環境下所對應的材料機械性質。根據鋯管研究結果顯示，當鋯管含氫量增加時其對應的彈性係數會隨之下降。進一步發現，隨著環境溫度的增加，彈性係數下降幅度也隨之增大；鋯管的蒲松比會從0.305上升至0.340。根據熔射鎳鋁合金膜層研究結果顯示，以大氣電漿熔射以及高速火焰熔射之鎳鋁合金膜層在常溫下其所對應的彈性係數值約為50至160GPa。當膜層製程中的氣體流速參數越快時，其對應的彈性係數會隨之上升；以高速火焰熔射技術製作膜層，其膜層彈性係數皆高於大氣電漿熔射技術所製作的膜層；當膜層厚度增加時，膜層彈性係數也會隨之上升。隨著環境溫度的增加，鎳鋁合金膜層的彈性係數會隨之下降，而蒲松比在部份膜層試片會隨之下降，其餘會隨之上升。
藉由本研究對高溫材料性質量測平台的開發，研究者可以藉由非接觸、非破壞以及即時量測的方式獲得結構材料在不同環境溫度下的材料性質定量資料，對於材料的製程及應用將有實質的貢獻。

關鍵字

非破壞檢測 ； 雷射超音波技術 ； 洗牌複合演進演算法 ； 鋯合金護套 ； 熔射技術 ； 高溫量測

並列摘要

This research is focused on the development of a noncontact, nondestructive high temperature material characterization platform consisting of a laser ultrasound measurement system followed by an inversion algorism for the extraction of material properties. In applying this platform, dispersion of Lamb waves or surface waves are measured with a laser laser-generation/laser-detection laser ultrasound technique (LUT). The platform is embedded with theoretical models for guided waves propagating along a plate, tube and multi-layered structure with coating. An inversion algorism based on shuffled complex evolution (SCE-UA) is used to extract mechanical properties from the measured dispersion spectra cooperating with theoretical model. With the advantages of nondestructive, noncontact and capable of remote measurements, this platform is applied for measurements at elevated temperature environments. Zircaloy cladding tubes of 0ppm, 200ppm and 500ppm hydrogen concentration (H.C.) used in nuclear fuel and thermal sprayed coatings of various manufacture parameters are tested and their material properties are obtained at the elevated temperature environments.
The Young’s modulus of Zircaloy cladding tubes will decrease while the hydrogen concentration increasing. At higher temperature environment, Young’s modulus decrease substantially of higher hydrogen concentration. On the other hand, the various manufacturing Ni-Al sprayed coatings at different temperature environment is reacted to dispersion spectrum of guided waves. The Young’s modulus of HVOF coatings are higher than APS coatings. This platform is potentially useful to probe the material characterization at high temperature environment in a remote and nondestructive way.

並列關鍵字

Nondestructive technique ； laser ultrasound technique ； guided waves ； SCE-UA algorithm ； Zircaloy cladding tube ； thermal spray technique ； temperature dependence

參考文獻

[1] C. E. Coleman and D. Harie, “The hydrogen embrittlement of alpha-Zirconium – A Review,” Journal of the Less Common Metals, vol. 11, 1966, pp. 168-185.

[2] S. B Wisner and R. B. Adamson, “Combine effects of radiation damage and hydrides on the ductility of Zircaloy-2,” Nuclear Engineering and Design, vol. 185, 1998, pp. 33-49.

[3] G. A. Bickel, L.W. Green, M.W.D. James, T.G. Lamarche, P.K. Lesson and H. Michel, “The determination of hydrogen and deuterium in Zr-2.5Nb material by hot vacuum extraction mass spectrometry,” Journal of Nuclear Materials, vol. 306, 2002, pp. 21-29.

[4] R. Yasuda, M. Matsubayashi, M. Nakata and K. Harada, “Application of neutron radiography for estimating concentration and distribution of hydrogen in Zircaloy cladding tubes,” Journal of Nuclear Materials, vol. 302, 2002, pp.156-164.

[8] 葉承鴻，單層圓管環向導波之頻散行為量測與材料參數反算，碩士論文，長庚大學，桃園縣， 2007。