本研究主要是以3D繪圖軟體Pro/Engineer及有限元素軟體ANSYS分析不同尖銳凹槽寬度及深度的SUS 304不鏽鋼薄壁圓管，在對稱曲度循環彎曲負載下的力學行為。其中尖銳凹槽分為兩種，一種為固定凹槽的深度，並改變凹槽的寬度，而另一種為固定凹槽的寬度，並改變凹槽的深度，而力學行為包含有彎矩-曲度和橢圓化-曲度的關係。由彎矩-曲度曲線圖中顯示，凹槽寬度對上述曲線沒有太大的影響，而凹槽深度越深，彎曲至某固定曲度時所需要的彎矩量就越小。由於循環應力-應變關係並未涵蓋循環硬化的現象，彎矩-曲度曲線並未顯現出循環硬化的現象。至於橢圓化-曲度的曲線圖中顯示，橢圓化會隨著循環圈數呈現非對稱棘齒狀的增加，而凹槽寬度對上述曲線沒有太大的影響，但尖銳凹槽的深度越深，彎曲至某固定曲度時所產生的橢圓化量就越大。

The main purpose of this thesis is to use the 3D mapping software Pro/Engineer and finite element software ANSYS to analyze SUS 304 stainless steel thin-walled tubes with different sharp-notched widths and depths subjected to symmetric-curvature cyclic bending. There are two kinds of sharp-notched case, one is fixed depth with variable widths, and the other is fixed width with variable depths. The mechanical behavior contains the moment-curvature and ovalization-curvature relationships. It is shown from the moment-curvature curve that the width does not affect the aforementioned curve relationship, however, the deeper the sharp-notch, the less amount of the moment to bend the tube to a certain magnitude of curvature. Because the cyclic stress-strain relationship using in this study doesn’t include the cyclic hardening, the moment-curvature curve also doesn’t show the cyclic hardening phenomenon. For the ovalization-curvature curve, the ovalization exhibits the unsymmetric-increasing ratcheting manner with the number of cycles. It is shown that the width does not affect the aforementioned curve, however, the deeper the sharp-notch, the larger amount of the ovalization to bend the tube to a certain magnitude of curvature.

S. Kyriakides and P. K. Shaw, “Response and Stability of
Elastoplastic Circular Pipe under Combined Bending and External Pressure,＂Int. J. Solids Struct., Vol.18, No.11, pp.957-973, 1982

2. P. K. Shaw and S. Kyriakides, “Inelastic Analysis of Thin-Walled Tubes under Cyclic Bending,＂Int. J. Solids Struct., Vol.21, No.11, pp.1073-1100, 1985

3. S. Kyriakides and P. K. Shaw, “Inelastic Buckling of Tubes under Cyclic Bending,＂ASME,J. of Pressure Vessel Tech., Vol.109, pp.169-178, 1987

4. E. Cornoa and S. Kyriakides, “On the Collapse of Inelastic Tubes under Combined Bending and Pressure,＂Int. J. Solids Struct., Vol.24,No.5, pp.505-535, 1988

5. E. E. Cornoa and S. Kyriakides, “An Expermental Investigation of the Degradation and Buckling of Circular Tubes under Cyclic Bending and external Pressure,＂Thin-Walled Structures, Vol.12, pp.229-263, 1991

6. S. Kyriakides and G. T. Ju, “Bifurcation And Localization Instabilities In Cylindrical Shells Under Bending-I. Experiment,＂Int. J. Solids Struct, Vol.29, No.9, pp.1117-1142, 1992

7. E. Cornoa and S. P. Vaze, “Buckling of Elastic-Plastic Square Tubes under Bending, ＂Int. J. Mech. Sci., Vol.38, No.7, pp.753-775, 1996

8. W. F. Pan and Y. S. Her, “Viscoplastic Collapse of Thin- Walled Tubes under Cyclic Bending,＂ASME, J. of Engineering Materials and Tech., Vol.120, pp.287-290, 1998

9. W. F. Pan, T. R. Wang and C. M. Hsu, “ A Curvature-Ovalization Measurement Apparatus for Circular Tubes under Cyclic Bending,＂Experimental Mechanics, Int.J., Vol.38, No.2, pp. 99-102, 1998

10. W. F. Pan and C. H. Fan, “An Experimental Stady on the Effect of Curvature-Rate at Preloading Stage on Subsequent Creep or Relaxation of Thin-Walled Tubes under Pure Bending,＂JSME Int. J., Series A, Vol.41, No.4, pp.525-531,1998

11. K.L. Lee, W.F. Pan and J.N. Kuo, “The Influence of the Diameter-to-Thickness Ratio of the Stability of Circular Tubes under Cyclic Bending,” International Journal of Solids and Structures, Vol. 38, pp. 2401-2413, 2001

12. 林俊宏, ”有限元素ANSYS分析圓管在循環彎曲負載下之力學行為,” 國立成功大學工程科學研究所碩士論文, 2006

13. R. Mahdavinejad, “Finite element analysis of machine and workpiece instability in turning,” International Journal of Machine Tools and Manufacture, Vol. 45, pp.753-760, 2005

14. Z. F. Wen, X. S. Jin and W. H. Zhang, “Contact-impact stress analysis of rail joint region using the dynamic finite element method,” Wear, Vol. 258, pp.1301-1309, 2005

15. M. M. Shokrieh and D. Rezaei, “Analysis and optimization of a composite leaf spring,” Composite Structures, Vol. 60, pp. 317-325, 2003

16. 陳建和, “TF-BGA錫球接點熱應力和損壞機制之研究,” 國立成功大學工程科學研究所碩士論文, 2002

17. M. X. Zhou, Q. A. Huang and Ming Qin, “Modeling, design and fabrication of a triple-layered capacitive pressure sensor,” Sensors and Actuators A：Physical, Vol.117, pp.71-81, 2005

18. M. M. Teymoori, E. Abbaspour-Sani, “Design and simulation of a novel electrostatic peristaltic micromachined pump for drug delivery application,” Sensors and Actuators A：Physical, Vol.117, pp.222-229, 2005

19. 鄭惟心, “全人工髖關節中超高分子聚乙烯元件之應力分佈：u有限元素法分析與臨床磨耗位置之比較,” 長庚大學機械工程研究所碩士論文, 2004

20. 溫從凱, “利用G/L方法探討WLCSP構裝含UBM錫球之疲勞壽命,” 國立成功大學工程科學研究所碩士論文, 2004

21. 林清安, Pro/Engineer Wildfire 3.0, 知城數位科技, 2005

22. ANSYS Inc. “ANSYS Users Manual,” 2003