音射檢測法（acoustic emission testing, AET）為一種非破壞檢測，利用試體破壞釋放的彈性波，轉換電子訊號後，記錄各項音射訊號與參數後加以分析，便能夠辨識物體的破壞機制與特徵。本研究使用尺寸為2×5×10mm的陶瓷、PMMA與複合試片，收集試片加載至破壞時的音射訊號，除了常見的參數分析:累積撞擊次數、訊號能量、裂縫模式分析，本研究亦使用統計分群模型－高斯混合模型（gaussian mixture model, GMM），提供音射訊號在辨識破裂模式更客觀的方法。
本研究結果顯示，陶瓷極限強度較高，承壓期間訊號量也較多，當載重歷時曲線產生鋸齒代表較大裂縫產生，對照能量圖能觀察到較大的值；PMMA極限強度較低，承壓期間訊號量少，大變形後才有訊號產生；複合試片整體結構較為脆弱，從能量圖可知，當產生較大的裂縫隨即發生毀滅性破壞。在裂縫模式分析中，3種材料表現相似，上升角（rise angle,RA）與平均頻率(average frequency, AF)大約分布在RA=0~5 ms/V、AF=0~200 kHz。GMM破裂模式分析結果3種材料皆以張力裂縫為主，陶瓷含有相對較多的剪力裂縫。訊號法分析可得到各材料的頻譜峰值的頻率域，統計結果各材料最常出現的頻率域依序為:陶瓷:175~200、450~475、100~125 kHz；PMMA為100~125、225~250、450~475 kHz；複合為450~475、175~200、125~175 kHz，並推測界面訊號約在125~175、200~225、450~525 kHz。

The purpose of this study is to characterize cracking sound of prosthetic material block made by ceramic and PMMA. The acoustic emission (AE) testing is one of the non-destructive test method, it can detect the AE signal of materials during loading and distinguish the failure mode of the material. The statistical analysis- gaussian mixture model(GMM) can provide smooth approximations to fit the AE data distribution, then divide the AE data into two categories: tensile and shear.
The results showed that the ultimate strength of ceramics is higher than PMMA ,and the amount of signals are also more than PMMA during the compressive test. As the load duration curves was observed the sawtooth shape, it represents the larger crack, and the higher value can be observed against the energy diagram. In the crack mode analysis, the three specimens performed similarly. The rise angle (RA) approximately distribute at RA=0~5 ms/V and the average frequency (AF) at AF=0~200 kHz. According to the GMM fracture mode analysis, all specimens are dominated by tension failure, and ceramics contain relatively more shear failure than PMMA. The signal-based analysis method can obtain the frequency domain of the spectral peak of each material. The statistical results show that the most frequency domain of each material : ceramic: 175~200, 450~475, 100~125 kHz; PMMA : 100~125, 225 ~250, 450~475 kHz; Composite : 450~475, 175~200, 125~175 kHz, and the signal that be obtained from the interface between PMMA and ceramic is estimated to be 125~175, 200~225, 450~525 kHz.

[1] 莊克士, 醫學影像物理學, 2 ed.: 合記圖書出版社, 2012.
[2] 黃洛豪, "牙科第五級複合樹脂填補在咬合力作用下之機械行為," 碩士, 機械工程研究所, 國立成功大學, 台南, 2015.
[3] 張群賢, "以音射法辨識牙本質與填補材料之破裂特徵," 碩士, 土木工程研究所, 國立成功大學, 台南, 2017.
[4] 陳圓蓉, "混凝土材料受高溫與再水化作用後之音射訊號特徵," 碩士, 土木工程研究所, 國立成功大學, 台南, 2018.
[5] 鄭峯昇, "音射法於自癒性混凝土損傷評估與破壞模式之探討," 碩士, 土木工程研究所, 國立成功大學, 台南, 2014.
[6] A. Hervás-García, M. Martínez-Lozano, J. Cabanes-Vila, A. Barjau-Escribano, and P. Fos-Galve, "Composite resins. A review of the materials and clinical indications," Med Oral Patol Oral Cir Bucal, vol. 11, pp. E215-20, 2006.
[7] Aldahdooh, M.A.A. and N. Muhamad Bunnori, Crack classification in reinforced concrete beams with varying thicknesses by mean of acoustic emission signal features. Construction and Building Materials, 2013. 45: p. 282-288.
[8] B. Yang, J. Guo, Q. Huang, Y. Heo, A. Fok, and Y. Wang, "Acoustic properties of interfacial debonding and their relationship with shrinkage stress in Class-I restorations," Dent Mater, vol. 32, pp. 742-8, Jun 2016.
[9] C. L. Lin, Y. H. Chang, and C. A. Pai, "Evaluation of failure risks in ceramic restorations for endodontically treated premolar with MOD preparation," Dent Mater, vol. 27, pp. 431-8, May 2011.
[10] C. A. Carrera, Y. C. Chen, Y. Li, J. Rudney, C. Aparicio, and A. Fok, "Dentin-composite bond strength measurement using the Brazilian disk test," J Dent, vol. 52, pp. 37-44, Sep 2016.
[11] Farhidzadeh, A., S. Salamone, and P. Singla, A probabilistic approach for damage identification and crack mode classification in reinforced concrete structures. Journal of Intelligent Material Systems and Structures, 2013. 24(14): p. 1722-1735.
[12] Grosse, C.U. and L.M. Linzer, Signal-Based AE Analysis, in Acoustic Emission Testing: Basics for Research - Applications in Civil Engineering, C. Grosse and M. Ohtsu, Editors. 2008, Springer Berlin Heidelberg: Berlin, Heidelberg. p. 53-99.

[13] Huang, M., L. Jiang, P. Liaw, C. Brooks, R. Seelev, and D. Klarstrom, Using acoustic emission in fatigue and fracture materials research. JOM, 1998. 50: p. 1-12.
[14] H. Li, J. Li, X. Yun, X. Liu, and A. S. Fok, "Non-destructive examination of interfacial debonding using acoustic emission," Dent Mater, vol. 27, pp. 964-71, Oct 2011.
[15] Hu, S., J. Lu, and F. Xiao, Evaluation of concrete fracture procedure based on acoustic emission parameters. Construction and Building Materials, 2013. 47: p. 1249-1256.
[16] J. C. Kapil, P. Datt, A. Kumar, K. Singh, V. Kumar, and P. K. Satyawali, "Multi-sensor couplers and waveguides for efficient detection of acoustic emission behavior of snow," Cold Regions Science and Technology, vol. 101, pp. 1-13, 2014.
[17] Kaiser, J., Erkenntnisse und Folgerungen aus der Messung von Geräuschen bei Zugbeanspruchung von metallischen Werkstoffen. Archiv für das Eisenhüttenwesen, 1953. 24(1-2): p. 43-45.
[18] K. V. Kiran, A. Tatikonda, K. Jhajharia, S. Raina, H. Lau, D. Katare, et al., "In vitro evaluation of the compressive strength of microhybrid and nanocomposites," 2014.
[19] K. Mohamed Bak and K. Kalaichelvan, "Evaluation of Failure Modes of Pure Resin and Single Layer of Adhesively Bonded Lap Joints Using Acoustic Emission Data," Transactions of the Indian Institute of Metals, vol. 68, pp. 73-82, 2015.
[20] M. Huang, L. Jiang, P. K. Liaw, C. R. Brooks, R. Seeley, and D. L. Klarstrom, "Using Acoustic Emission in Fatigue and Fracture Materials Research," JOM, vol. 50, pp. 1-14, 1998.
[21] Malhotra, V.M. and N.J. Carino, Handbook on Nondestructive Testing of Concrete. 2004: CRC Press.
[22] N. Ereifej, N. Silikas, and D. C. Watts, "Initial versus final fracture of metal-free crowns, analyzed via acoustic emission," Dent Mater, vol. 24, pp. 1289-95, Sep 2008.
[23] N. Ilie and R. Hickel, "Resin composite restorative materials," Aust Dent J, vol. 56 Suppl 1, pp. 59-66, Jun 2011.
[24] N.-S. Choi, J.-U. Gu, and K. Arakawa, "Acoustic emission characterization of the marginal disintegration of dental composite restoration," Composites Part A: Applied Science and Manufacturing, vol. 42, pp. 604-611, 2011.
[25] N. Garg and A. Garg, Textbook of operative dentistry, 2 ed.: JAYPEE, 2013.
[26] N. Y. Cho, J. L. Ferracane, and I. B. Lee, "Acoustic emission analysis of tooth-composite interfacial debonding," J Dent Res, vol. 92, pp. 76-81, Jan 2013.
[27] Ohtsu, M., Acoustic emission theory for moment tensor analysis. Research in Nondestructive Evaluation, 1995. 6(3): p. 169-184.
[28] Ohtsu, Masayasu, and S. Yuyama. "Recommended practice for in situ monitoring of concrete structures by acoustic emission." 15 th International Acoustic Emission Symposium. 2000.
[29] Ohno, K. and M. Ohtsu, Crack classification in concrete based on acoustic emission. Construction and Building Materials, 2010. 24(12): p. 2339-2346.
[30] P. Alander, "Acoustic emission analysis of fiber-reinforced composite in flexural testing," Dental Materials, vol. 20, pp. 305-312, 2004.
[31] Prem, P.R. and A.R. Murthy, Acoustic emission monitoring of reinforced concrete beams subjected to four-point-bending. Applied Acoustics, 2017. 117: p. 28-38.
[32] Reynolds, D.A. and R.C. Rose, Robust text-independent speaker identification using Gaussian mixture speaker models. IEEE Transactions on Speech and Audio Processing, 1995. 3(1): p. 72-83.
[33] Richiardi, J. and A. Drygajlo, Gaussian Mixture Models for on-line signature verification, in Proceedings of the 2003 ACM SIGMM workshop on Biometrics methods and applications. 2003, ACM: Berkley, California. p. 115-122.
[34] R. J. Kim, Y. J. Kim, N. S. Choi, and I. B. Lee, "Polymerization shrinkage, modulus, and shrinkage stress related to tooth-restoration interfacial debonding in bulk-fill composites," J Dent, vol. 43, pp. 430-9, Apr 2015.
[35] Shiotani, T., Parameter Analysis, in Acoustic Emission Testing: Basics for Research - Applications in Civil Engineering, C. Grosse and M. Ohtsu, Editors. 2008, Springer Berlin Heidelberg: Berlin, Heidelberg. p. 41-51.
[36] S. F. Chuang, C. H. Chang, and T. Y. Chen, "Contraction behaviors of dental composite restorations--finite element investigation with DIC validation," J Mech Behav Biomed Mater, vol. 4, pp. 2138-49, Nov 2011.
[37] Standard Guide for Determining the Reproducibility of Acoustic Emission Sensor Response. 2015, American Society for Testing and Materials.
[38] V. Arumugam, S. Sajith, and A. J. Stanley, "Acoustic Emission Characterization of Failure Modes in GFRP Laminates Under Mode I Delamination," Journal of Nondestructive Evaluation, vol. 30, pp. 213-219, 2011.