MWCNT Oranının MWCNT ile güçlendirilmiş Al2O3 Matrisli Nanokompozitlerin Mikroyapı ve Mekanik Özelliklerine Etkisi

Bu çalışmada, ağırlıkça %0,0 dan %15,0’e kadar farklı oranlarda aktive edilmiş çok duvarlı karbon nanotüp (MWCNT) takviyeli ve alümina Al2O3 matrislinanokompozitler başarılı bir şekilde üretilmiştir. Nano boyuttaki (80 nm) Al2O3 tozları ve MWCNT’ler yüksek hızlı gezegensel bilyeli değirmende karıştırılmış, ardından soğuk şekillendirilmiş ve 1600o C’de argon atmosferinde 120 dakika süre ile sinterlenmiştir. Üretilen nanokompozitlerin mikroyapıları taramalı elektron mikroskobu (SEM) kullanılarak kırık yüzeylerden incelenmiştir. MWCNT ilavesinin kristal yapı ve üzerindeki etkisi X-ışınları difraktometresi (XRD) kullanılarak ortaya çıkarılmıştır. Mekanik özellikleri vickers mikrosertlik yöntemi kullanılarak belirlenmiştir. Kırılma toklukları ise vickers indenter metodu kullanılarak incelenmiştir. Yapılan kırılma tokluğu deneyleri sonucunda MWCNT ilavesi Al2O3 esaslı seramik malzemenin kırılma tokluğunu belirgin bir şekilde artırdığı görülmüştür. %2,5 MWCNT ilavesi seramik matrisli nanokompozit yapının kırılma tokluğunu katkısız Al2O3 ile kıyaslandığında %182,5 oranında artırmıştır.

Anahtar Kelimeler:

Nanokompozit, MWCNT, Al2O3, Kırılma tokluğu, Sinterleme

Effect of MWCNT Ratio on Microstructure and Mechanical Properties of MWCNT Reinforced Al2O3 Matrix Nanocomposites

In this study, multi walled carbon nanotube (MWCNT) reinforced alumina (Al2O3) ceramic matrix nanocomposites containing MWCNT from 0.0 wt.% to 15.0 wt. % have been successfully produced. Nano size (80 nm) Al2O3 powders and MWCNT’s have mixed with high velocity planetary ball milling and then green compacted and sintered at 1600 oC for 120 min in flowing Argonne atmosphere. Microstructure of produced nano composites have investigated with scanning electron microscope (SEM) from fracture surfaces. Effect of MWCNT addition on crystal structure were investigated via X-ray diffractometer (XRD). Microhardness test was carried out for determine mechanical properties of ceramic matrix nano composite mechanical properties. Vickers indenter test method was used for determining fracture toughness properties. MWCNT addition was significantly increased fracture toughness of Al2O3 based structure. % 2.5 wt. % MWCNT addition was increased 182.5 wt. % fracture toughness when the compering unreinforced Al2O3 structure.

Keywords:

Nanocomposites, MWCNT, Al2O3, Fracture toughness, sintering,

PDF

___

[1] S. Maensiri, P. Laokul, J. Klinkaewnarong, and V. Amornkitbamrung, “Carbon nanofiber-reinforced alumina nanocomposites: Fabrication and mechanical properties,” Materials Science and Engineering: A, vol. 447, no. 1–2, pp. 44–50, Feb. 2007.
[2] I. Ahmad et al., “Multi-walled carbon nanotubes reinforced Al2O3 nanocomposites: Mechanical properties and interfacial investigations,” Composites Science and Technology, vol. 70, no. 8, pp. 1199–1206, Aug. 2010.
[3] M. Michálek, M. Kašiarová, M. Michálková, and D. Galusek, “Mechanical and functional properties of Al2O3–ZrO2–MWCNTs nanocomposites,” Journal of the European Ceramic Society, vol. 34, no. 14, pp. 3329–3337, Nov. 2014.
[4] G.-D. Zhan, J. D. Kuntz, J. Wan, and A. K. Mukherjee, “Single-wall carbon nanotubes as attractive toughening agents in alumina-based nanocomposites,” Nature Materials, vol. 2, no. 1, pp. 38–42, Jan. 2003.
[5] S. C. Zhang, W. G. Fahrenholtz, G. E. Hilmas, and E. J. Yadlowsky, “Pressureless sintering of carbon nanotube–Al2O3 composites,” Journal of the European Ceramic Society, vol. 30, no. 6, pp. 1373–1380, Apr. 2010.
[6] T. Wei, Z. Fan, G. Luo, and F. Wei, “A new structure for multi-walled carbon nanotubes reinforced alumina nanocomposite with high strength and toughness,” Materials Letters, vol. 62, no. 4–5, pp. 641–644, Feb. 2008.
[7] K. T. Kashyap and R. G. Patil, “On Young’s modulus of multi-walled carbon nanotubes,” Bulletin of Materials Science, vol. 31, no. 2, pp. 185–187, Apr. 2008.
[8] A. Peigney, C. Laurent, E. Flahaut, and A. Rousset, “Carbon nanotubes in novel ceramic matrix nanocomposites,” Ceramics International, vol. 26, no. 6, pp. 677–683, Jul. 2000.
[9] E. Flahaut, A. Peigney, C. Laurent, C. Marlière, F. Chastel, and A. Rousset, “Carbon nanotube–metal–oxide nanocomposites: microstructure, electrical conductivity and mechanical properties,” Acta Materialia, vol. 48, no. 14, pp. 3803–3812, Sep. 2000.
[10] A. Peigney, C. Laurent, O. Dumortier, and A. Rousset, “Carbon Nanotubes±Fe±Alumina Nanocomposites. Part I: In¯uence of the Fe Content on the Synthesis of Powders,” p. 10.
[11] Z. Han and A. Fina, “Thermal conductivity of carbon nanotubes and their polymer nanocomposites: A review,” Progress in Polymer Science, vol. 36, no. 7, pp. 914–944, Jul. 2011.
[12] L. Shi, C. F. Sun, P. Gao, F. Zhou, and W. M. Liu, “Electrodeposition and characterization of Ni–Co–carbon nanotubes composite coatings,” Surface and Coatings Technology, vol. 200, no. 16–17, pp. 4870–4875, Apr. 2006.
[13] R. Karslioglu and H. Akbulut, “Comparison microstructure and sliding wear properties of nickel–cobalt/CNT composite coatings by DC, PC and PRC current electrodeposition,” Applied Surface Science, vol. 353, pp. 615–627, Oct. 2015.
[14] S. I. Cha, K. T. Kim, K. H. Lee, C. B. Mo, and S. H. Hong, “Strengthening and toughening of carbon nanotube reinforced alumina nanocomposite fabricated by molecular level mixing process,” Scripta Materialia, vol. 53, no. 7, pp. 793–797, Oct. 2005.
[15] S.-Y. Lee, J.-I. Kim, and S.-J. Park, “Activated carbon nanotubes/polyaniline composites as supercapacitor electrodes,” Energy, vol. 78, pp. 298–303, Dec. 2014.
[16] V. Puchy, P. Hvizdos, J. Dusza, F. Kovac, F. Inam, and M. J. Reece, “Wear resistance of Al2O3–CNT ceramic nanocomposites at room and high temperatures,” Ceramics International, vol. 39, no. 5, pp. 5821–5826, Jul. 2013.
[17] S. Maensiri, P. Laokul, J. Klinkaewnarong, and V. Amornkitbamrung, “Carbon nanofiber-reinforced alumina nanocomposites: Fabrication and mechanical properties,” Materials Science and Engineering: A, vol. 447, no. 1–2, pp. 44–50, Feb. 2007.
[18] G.-D. Zhan and A. K. Mukherjee, “Carbon Nanotube Reinforced Alumina-Based Ceramics with Novel Mechanical, Electrical, and Thermal Properties,” International Journal of Applied Ceramic Technology, vol. 1, no. 2, pp. 161–171, 2004.
[19] M. R. Gallas, Y. C. Chu, and G. J. Piermarini, “Calibration of the Raman effect in α–Al 2 O 3 ceramic for residual stress measurements,” Journal of Materials Research, vol. 10, no. 11, pp. 2817–2822, Nov. 1995.
[20] E. D. Dikio, N. D. Shooto, F. T. Thema and A. M. Farah “Raman and TGA Study of Carbon Nanotubes Synthesized Over Mo/Fe Catalyst on Aluminium Oxide, Calcium Carbonate and Magnesium Oxide Support,” Chemical Science Transactions, vol. 2, no. 4, Oct. 2013.