Deformation of carbon fiber-reinforced plastic deformation under the time-varying loads

Аuthors

Ruslantsev A. N.^1*, Dumansky A. M.^2**

1. Bauman Moscow State Technical University, MSTU, 5, bldg. 1, 2-nd Baumanskaya str., Moscow, 105005, Russia
2. Mechanical Engineering Research Institute of the Russian Academy of Sciences, 4, M. Khariton'evskii per., Moscow, 101990, Russia

*e-mail: andreiruslantsev@gmail.com
**e-mail: alduman@rambler.ru

Abstract

Rheological effects such as creep and relaxation may appear in the material when operating under long-time load. This can lead to a delayed fracture, so it is important to analyze the regularities of polymer composite materials deformation with account to the time factor. The presented article considers models implemented for describing rheological effects, shows their advantages and disadvantages.

The most common cases of loading can be described by the relationships of hereditary mechanics. Besides the fact that the hereditary approach is the most common form of a relationships between stresses and deformations at time varying loads, it allows identify a number of interrelated functions characterizing the material.

A model based on the matrix equations of the theory of laminated plates and relations of a hereditary type is proposed. It allows establish the dependence of deformations from time under time-varying loading.

To reveal time effects, the test for creep and relaxation of BMI-3/3692 carbon fiber-reinforced plastics samples with reinforcement scheme [±45°] and KMU-4L with reinforcement scheme [±20°] were performed. The BMI-3/3692 samples were tested for creep at time-varying loading also. The KMU-4L samples were tested for creep and relaxation. Resistive strain gages were employed to register longitudinal and transverse deformations. Nonlinearity and hysteresis are appearing on the stress-strain diagrams of the tested samples. Likewise, the diagrams of stresses and deformations are essentially dissimilar to each other, which can be explained by time-dependent factors.

Calculation for BMI-3/3692 carbon plastics with reinforcement scheme [± 45°] and KMU-4L with reinforcement scheme [± 20°] was performed employing the model proposed in the work. The Abel kernel was chosen as a creep kernel. Rabotnov kernel was used as a relaxation kernel.

Mechanical characteristics of the BMI-3/3692 carbon plastic were determined: E₁ = 84 GPa, E₂ = 80 GPa, ν₁₂ = 0.04. G₁₂ = 7.5 GPa. . The kernel parameters were determined by the least-squares method. Minimum of disparity of computed and experimental parameters was determined numerically. The following parameters values were obtained: α = –0.7, β = –0.05, k = 800.

The elastic characteristics of the of KMU-4 carbon plastic monolayer were determined: E₁ = 150 GPa, E₂ = 4 GPa, ν₁₂ = 0.32. G₁₂ = 3.3 GPa. The kernel parameters were also determined numerically: α = –0.8, β = –0.05, k = 150.

The article presents the graphs demonstrating a good correspondence between calculated and experimental data.

The proposed model can be used to calculate the stress-strain state of composite structures while long-term deformation.

Keywords:

carbon fiber-reinforced plastic, hereditary mechanics, creep, recovery, theory of laminated plates

References

1. Schapery R.A. Viscoelastic behavior and analysis of composite materials, Mechanics of Composite Materials, 1974, vol. 2, pp. 86 – 168.

2. Deng S., Li X., Weitsman Y. Time-Dependent Deformation of Stitched T300 Mat / Urethane 420 IMR Cross-Ply Composite Laminates, Mechanics of Time-Dependent Materials, 2003, no. 7, pp. 41 – 69.

3. Koltunov M.A. Polzuchest’ i relaksatsiya (Creep and relaxation), Moscow, Vyshaya shkola, 1976, 277 p.

4. Kawai M., Masuko Y., Sagawa T. Off-axis tensile creep rupture of unidirectional CFRP laminates at elevated temperature, Composites: Part A, 2006, no. 37, pp. 257 – 269.

5. Yao Z., Wua D., Chen C., Zhang M. Creep behavior of polyurethane nanocomposites with carbon nanotubes, Composites: Part A, 2013, no. 50, pp. 65 – 72.

6. Yahyaei-Moayyed M., Taheri F. Experimental and computational investigations into creep response of AFRP reinforced timber beams, Composite Structures, 2011, no. 93, pp. 616 – 628.

7. Sokolov E.A. The possibilities of predicting the creep properties of the laminate organoplastic unidirectional fiber reinforced materials, Mechanics of Composite Materials, 1980, no. 1, pp 142 – 147.

8. Du Y., Yan N., Kortschot M. An experimental study of creep behavior of lightweight natural fi ber-reinforced polymer composite / honeycomb core sandwich panels, Composite Structures, 2013, no. 106, pp. 160 – 166.

9. Rabotnov Yu.N., Papernik A.Kh., Stepanychev E.I. Mekhanika polimerov, 1971, no. 3, pp. 391 – 397.

10. Rabotnov Yu.N., Papernik A.X., Stepanychev E.I. Mekhanika polimerov, 1974, no. 4, pp. 624 – 628.

11. Balevicius R., Marciukaitis G. Linear and Non-linear Creep models for a multi-layered concrete composite, Archives of civil and mechanical engineering, 2013, no. 13, pp. 472 – 490.

12. Yanson Yu.O., Dmitrienko I.P., Zelin V.I. Mekhanika kompozitnykh materialov, 1983, no. 4, pp. 610 – 613.

13. Maksimov R.D., Plume E.Z. Mekhanika kompozitnykh materialov, 1982, no. 6, pp. 1081 – 1089.

14. Plume Je.Z. Mehanika kompozitnyh materialov, 1985, no. 3, pp. 431 – 436.

15. Hohlov A.V. Trudy MAI, 2016, no. 91, available at: http://trudymai.ru/eng/published.php?ID=75559

16. Rabotnov Ju.N. Jelementy nasledstvennoj mehaniki tverdyh tel (Elements of hereditary solids mechanics), Moscow, Nauka, 1977, 384 p.

17. Ruslantsev A.N., Portnova Ya.M., Tairova L.P., Dumansky A.M. Analisys of mechanical properties anisotropy of nanomodified carbon fiber-reinforced woven composites, IOP Conference Series: Material Science and Engineering (MSE), 2016, vol. 153. DOI: 10.1088/1757-899.

18. Dumanskii A.M., Ruslantsev A.N., Karaseva A.A. Materialy IX Mezhdunarodnoi konferentsii po neravnovesnym protsessam v soplakh i struyakh (NPNJ’2012), Alushta, 2012, pp 363 – 365.

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