Predicting the In-plane Elastic Constants of Diamond Braided Composites

Abstract

An analytical model based upon repeat unit cell approach is proposed to predict the in-plane elastic constants of two dimensional diamond braided composites. A new geometrical model is developed which considers the yarn undulation and inter-yarn gap in a diamond braided fabric reinforced composite. The actual state of yarns in composites is modeled by the use of sinusoidal shape functions, which employ parameters such as braid construction, yarn geometry, inter-yarn gap and overall volume fraction to quantify the geometry of braided fabric. Stiffness is predicted by calculating the engineering constants for each subcell followed by averaging it over the repeat unit cell’s volume using a combination of iso-stress and iso-strain conditions. Composites using four different fabric architectures are fabricated and tested in tensile mode to verify the model. The experimental results indicate reasonable correlation with predicted results. Parametric study is conducted over a range of structurally possible geometrical parameters to study the effects of braiding angle, yarn aspect ratio and gap on the in-plane elastic properties of the textile composite.

Keywords

fabricreinforcedcomposites diamondbraid unitcell averagingtechnique stiffnessmodeling

Get full access to this article

View all access options for this article.

References

1. Ganesh, V. K. , S. Ramakrishna , P. L. Loh , C. L. Chew and S. H. Teoh . 1998. “Functionally Graded Composites for Dental Applications,” Proceedings of 1st Asian-Australasian Conference on Composite Materials (ACCM),Osaka, Japan.

2. Ma, C. L. , J. M. Yang and T. W. Chou . 1986. “Elastic Stiffness of Three-Dimensional Braided Textile Structural Composites,” Composites Materials: Testing and Design (7th Conference),ASTM 893, Philadelphia, pp. 404-421.

3. Yang, J. M. , C. L. Ma and T. W. Chou . 1986. “Fiber Inclination Model of Three-Dimensional Textile Structural Composites,” Journal of Composite Materials,20(5):472-483.

4. Byun, J. H. , T. J. Whitney , G. W. Du and T. W. Chou . 1991. “Analytical Characterization of Two-Step Braided Composites,” Journal of Composite Materials,25(12):1599-1618.

5. Masters, J. E. , R. L. Foye , C. M. Pastore and Y. A. Gowayed . 1993. “Mechanical Properties of Triaxially Braided Composites: Experimental and Analytical Results,” Journal of Composites Technology and Research,1993, 15(2):112-122.

6. Smith, L. V. and S. R. Swanson . 1993. “Response of Braided Composite under Compressive Loading,” Composites Engineering,3:1165-1184.

7. Smith, L. V. and S. R. Swanson . 1995. “Micro-Mechanics Parameters Controlling the Strength of Braided Composites,” Composites Science and Technology,54(2):177-184.

8. Yang, J. M. and T. W. Chou . 1989. “Thermo-Elastic Analysis of Triaxial Woven Fabric Composites,” Textile Structural Composites, Chou, T. W. and Ko, F. K. (Eds.), Elsevier, pp. 265-277.

9. Tsai, J. S. , S. J. Li and L. J. Lee . 1998. “Microstructural Analysis of Composite Tubes Made from Braided Preform and Resin Transfer Molding,” Journal of Composite Materials,32(9):829-850.

10.

10. Naik, R. A. 1995. “Failure Analysis of Woven and Braided Fabric Reinforced Composites,” Journal of Composite Materials,29(17):2334-2363.

11.

11. Naik, R. A. 1996. “Analysis of Woven and Braided Fabric Composites,” Composite Materials: Testing and Design (Twelfth Volume),ASTM STP 1274, R. B. Deo and C. R. Saff , Eds., American Society for Testing and Materials, pp. 239-263.

12.

12. Naik, R. A. , P. J. Ifju and J. E. Masters . 1994. “Effect of Fiber Architecture Parameters on Deformation Fields and Elastic Moduli of 2-D Braided Composites,” Journal of Composite Materials,28(7):656-681.

13.

13. Dadkhah, M. S. , J. G. Flintoff , T. Kniveton and B. N. Cox . 1995. “Simple Models for Triaxially Braided Composites,” Composites,26(8):561-577.

14.

14. Masters, J. E. and P. G. Ifju . 1996. “A Phenomenological Study of Triaxially Braided Textile Composites Loaded in Tension,” Composite Science and Technology,56:347-358.

15.

15. Naik, N. K. and V. K. Ganesh . 1992. “Prediction of On-Axes Elastic Properties of Plain Weave Fabric Composites,” Composite Science and Technology,45:135-152.

16.

16. Kalidindi, S. R. and A. Abusafieh . 1996. “Longitudinal and Transverse Moduli and Strengths of Low Angle 3-D Braided Composites,” Journal of Composite Materials,30(8):885-905.

17.

17. Smith, L. V. and S. R. Swanson . 1996. “Strength Design with 2-D Triaxial Braid Textile Composites,” Composite Science and Technology,56:359-365.