بررسی اثر عیوب ساختار اتمی بر ضریب انبساط حرارتی نانولوله کربنی زیگزاگ و آرمچیر به روش دینامیک مولکولی
محورهای موضوعی : فرآیندهای شبیه سازیفرشید آقاداودی 1 , حسین گلستانیان 2
1 - استادیار، گروه مکانیک، دانشگاه آزاد اسلامی، واحد خمینی شهر، خمینیشهر، ایران
2 - استاد، دانشکده فنی مهندسی، دانشگاه شهرکرد، شهرکرد، ایران
کلید واژه: انولوله کربنی ضریب انبساط حرارتی دینامیک مولکولی عیوب استون, والس,
چکیده مقاله :
خواص مکانیکی و فیزیکی نانولولههای کربنی به اندازه و ساختار اتمی وابسته است. تعیین دقیق خواص نانولولههای کربنی از جمله ضریب انبساط گرمایی به دلیل محدودیتهای روشهای آزمایشگاهی به لحاظ عملی با مشکلاتی توأم است. در این مطالعه از روش دینامیک مولکولی برای بررسی ضریب انبساط حرارتی در تعدادی از نمونههای نانولوله کربنی که دارای قطر متفاوت و ساختار آرمچیر و زیگزاگ هستند، استفاده شده است. همچنین اثر عیوب ساختار اتمی شامل عیب استون- والس و جای خالی بر ضریب انبساط حرارتی و خواص الاستیک مکانیکی طولی نانولوله کربنی مورد بررسی قرار گرفته است. تابع پتانسیل مورد استفاده در شبیهسازی COMPASS بوده است. نتایج بهدستآمده نشان میدهد که اندازه و نوع ساختار نانولوله کربنی بر مقدار ضریب انبساط حرارتی مؤثر است. ضریب انبساط حرارتی برای نانولوله کربنی (7 و 7) در دمای 800 کلوین برابر با K-1 6.34 محاسبه شده است که تطبیق خوبی با نتایج مطالعات آزمایشگاهی در سایر مطالعات نشان میدهد. نتایج حاصل نشان میدهد که وجود عیوب ساختار اتمی عیب جای خالی بازسازی نشده، در بیشتر موارد باعث افزایش ضریب انبساط حرارتی شده است که این افزایش در نانولوله کربنی (0 و 7) برابر با 65% بوده است. عیب جای خالی بیشتر از عیب استون- والس در تغییرات ضریب انبساط حرارتی مؤثر است. نتایج نشان میدهد خواص الاستیک نیز در نمونه مورد بررسی در اثر وجود عیب جای خالی در راستای طولی به اندازه 22% نسبت به نمونه بدون عیب تضعیف شده است.
The mechanical and physical properties of carbon nanotubes depend on their size and atomic structure. Accurate determination of the properties of carbon nanotubes, including the coefficient of thermal expansion, has many practical problems due to the limitations of laboratory methods. In this study, molecular dynamics method has been used to investigate and extract the properties of thermal expansion coefficient in a number of samples of carbon nanotubes that have different diameters and armchair and zigzag structures. In this study, the effect of atomic structure defects including Stone–Wales and vacancy defects on the coefficient of thermal expansion and longitudinal elastic mechanical properties of carbon nanotubes have been investigated. The potential function used in COMPASS simulation. Based on the obtained results, the coefficient of thermal expansion for CNT (7,7) at a temperature of 800 K is calculated at about 6.34 , which shows a good agreement with the results of laboratory studies. Also, the presence of defects in the atomic structure, including the defect of the non-reconstructed vacancy, in most cases has increased the coefficient of thermal expansion, which has been equal to 65% in CNT (0, 7). The vacancy defect is more effective than the Stone-Walsh defect in changing the coefficient of thermal expansion. The results show that the elastic properties of the CNT case study are also weakened by 22% due to the defect of the vacancy in the longitudinal direction.
[1] S. Iijima, "Helical microtubules of graphitic carbon", Nature, vol. 354, no. 6348, pp. 56-58, 1991.
[2] Y. Tian, "Optical properties of single-walled carbon nanotubes and nanobuds", 2012.
[3] R. S. Ruoff & D. C. Lorents, "Mechanical and thermal properties of carbon nanotubes", Carbon, vol. 33, no. 7, pp. 925-930, 1995.
[4] E. A. Laird, et al. "Quantum transport in carbon nanotubes", Reviews of Modern Physics, vol. 87, no. 3, pp. 703, 2015.
[5] Z. Tang, et al. "Superconductivity in 4 angstrom single-walled carbon nanotubes", Science, vol. 292, no. 5526, pp. 2462-2465, 2001.
[6] Z. M. Ghahfarokhi & H. Golestanian, "Effects of nanotube helical angle on mechanical properties of carbon nanotube reinforced polymer composites", Computational Materials Science, vol. 50, no. 11, pp. 3171-3177, 2011.
[7] E. T. Thostenson & T. Chou, "On the elastic properties of carbon nanotube-based composites: modelling and characterization", Journal of Physics D: Applied Physics, vol. no. 36, 5, pp. 573, 2003.
[8] E. T. Thostenson, Z. Ren & T. W. Chou, "Advances in the science and technology of carbon nanotubes and their composites: a review", Composites science and technology, vol. 61, no. 13, pp. 1899-1912, 2001.
[9] S. J. Tans, A. R. Verschueren & C. Dekker, "Room-temperature transistor based on a single carbon nanotube", Nature, vol. 393, no. 6680, pp. 49-52, 1998.
[10] J. Appenzeller, et al. "Field-modulated carrier transport in carbon nanotube transistors", Physical Review Letters, vol. 89, no. 12, pp. 126801, 2002.
[11] P. Alipour, et al. "Modeling different structures in perturbed Poiseuille flow in a nanochannel by using of molecular dynamics simulation: Study the equilibrium", Physica A: Statistical Mechanics and its Applications, vol. 515, pp. 13-30, 2019.
[12] D. T. Semiromi & A. Azimian, "Nanoscale Poiseuille flow and effects of modified Lennard–Jones potential function". Heat and mass transfer, vol. 46, 7, pp. 791-801, 2010.
[13] D. Roustazadeh, F. Aghadavoudi & A. Khandan, "A synergic effect of CNT/Al2O3 reinforcements on multiscale epoxy-based glass fiber composite: fabrication and molecular dynamics modeling", Molecular Simulation, vol. 46, no. 16, pp. 1308-1319, 2020.
[14] L. Espinosa-Vega, et al. "Determination of the thermal expansion coefficient of single-wall carbon nanotubes by Raman spectroscopy", Spectroscopy Letters, vol. 48, no. 2, pp. 139-143, 2015.
[15] L. Song, et al. "Temperature dependence of Raman spectra in single-walled carbon nanotube rings", Applied Physics Letters, vol. 92, no. 12, pp. 121905, 2008.
[16] A. V. Dolbin, et al. "Radial thermal expansion of single-walled carbon nanotube bundles at low temperatures", Low Temperature Physics, vol. 34, no. 8, pp. 678-679, 2008.
[17] M. Tahmasebipour, R. Ahmadi & M. Modarres, "Analysis of thermo-mechanical behavior of gold nanowire by using molecular dynamics method", Advanced Processes in Materials Engineering, vol. 13, no. 1, pp. 91-101, 2019.
[18] L. Chang, et al. "Molecular dynamics study of strain rate effects on tensile behavior of single crystal titanium nanowire", Computational Materials Science, vol. 128, pp. 348-358, 2017.
[19] N. R. Raravikar, et al. "Temperature dependence of radial breathing mode Raman frequency of single-walled carbon nanotubes", Physical Review B, vol. 66, 23, pp. 235424, 2002.
[20] H. Jiang, et al. "Thermal expansion of single wall carbon nanotubes", J. Eng. Mater. Technol, vol. 126, no. 3, pp. 265-270, 2004.
[21] K. Shirasu, et al. "Negative axial thermal expansion coefficient of carbon nanotubes: Experimental determination based on measurements of coefficient of thermal expansion for aligned carbon nanotube reinforced epoxy composites", Carbon, vol. 95, pp. 904-909, 2015.
[22] Q. Lu & B. Bhattacharya, "Effect of randomly occurring Stone–Wales defects on mechanical properties of carbon nanotubes using atomistic simulation", Nanotechnology, vol. 16, no. 4, pp. 555, 2005.
[23] N. Pugno, F. Bosia & A. Carpinteri, "Size effects on the strength of nanotube bundles", Measurement Science and Technology, vol. 20, no. 8, pp. 084028, 2009.
[24] M. Haghighi, et al. "Effects of defects and functional groups on graphene and nanotube thermoset epoxy-based nanocomposites mechanical properties using molecular dynamics simulation", Polymers and Polymer Composites, pp. 0967391120929075, 2020.
[25] P. G. Collins, "Defects and disorder in carbon nanotubes". Oxford University Press: Oxford, 2010.
[26] S. Yu, S. Yang & M. Cho, "Multi-scale modeling of cross-linked epoxy nanocomposites". Polymer. vol. 50, no. 3, pp. 945-952, 2009.
[27] K. Sharma, K. K. Saxena & M. Shukla, "Effect of multiple Stone-Wales and Vacancy defects on the mechanical behavior of carbon nanotubes using Molecular Dynamics", Procedia Engineering, vol. 38, pp. 3373-3380, 2012.
[28] A. Shokuhfar & B. Arab, "The effect of cross linking density on the mechanical properties and structure of the epoxy polymers: molecular dynamics simulation", Journal of molecular modeling. vol. 19, no. 9, pp. 3719-3731, 2013.
[29] A. Fluegel, et al. "Density and thermal expansion calculation of silicate glass melts from 1000 C to 1400 C", Physics and Chemistry of Glasses-European Journal of Glass Science and Technology Part B, vol. 49, no. 5, pp. 245-257, 2008.
[30] T. Natsuki, K. Tantrakarn & M. Endo, "Effects of carbon nanotube structures on mechanical properties". Applied Physics A, vol. 79, no. 1, pp. 117-124, 2004.
[31] J. P. Salvetat, et al. "Mechanical properties of carbon nanotubes", Applied Physics A, vol. 69, no. 3, pp. 255-260, 1999.
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