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Abstrak :
Materials science and engineering of carbon, fundamentals provides a comprehensive introduction to carbon, the fourth most abundant element in the universe. The contents are organized into two main parts. Following a brief introduction on the history of carbon materials, Part 1 focuses on the fundamental science on the preparation and characterization of various carbon materials, and Part 2 concentrates on their engineering and applications, including hot areas like energy storage and environmental remediation. The book also includes up-to-date advanced information on such newer carbon-based materials as carbon nanotubes and nanofibers, fullerenes and graphenes.

Abstrak :
TKKS merupakan limbah perkebunan kelapa sawit dengan kandungan serat selulosa yang dapat dimanfaatkan sebagai bahan penyusun komposit. Komposit serat alami dengan matriks epoksi dikenal memiliki resistansi kimia yang baik. Penambahan carbon nanotube pada komposit diketahui melalui banyak penelitian dapat meningkatkan sifat mekanik. Pada penelitian ini dilakukan penambahan carbon nanotube pada komposit serat TKKS dengan matriks epoksi sebanyak 0,1%, 0,5%, dan 1% dari berat matriks yang digunakan. Serat TKKS didapatkan dengan metode chemical retting. Untuk meningkatkan kompabilitas, fungsionalisasi dan perlakuan carbon nanotube dan serat TKKS dilakukan dengan metode mild acid oxidation dan silane coupling agent dan terbukti tidak merusak struktur dan ukuran carbon nanotube. Penambahan carbon nanotube meningkatkan kekuatan tarik komposit serat TKKS dengan matriks epoksi sebesar 10,03%, 4,75%, dan 7,75% dan kekuatan tekuk sebesar 51,64%, 65,8%, dan 105,9% masing-masing untuk penambahan carbon nanotube sebanyak 0,1%, 0,5%, dan 1% dari berat matriks yang digunakan. ......Empty palm oil fruit bunch fiber is the side product of palm oil cultivication that contain cellulose fiber. This kind of fiber is usually used as composite reinforcement. Natural fiber reinforced composite with epoxy matrices well known of its chemical stability. Addition of carbon nanotube also known to strengthen epoxy based composites. In this research, carbon nanotube is added as much as 0,1%, 0,5%, and 1% wt in matrices. The empty palm oil fruit bunch fiber is prepared by chemical retting process. Functionalization and surface treatment of carbon nanotube and natural fiber with mild acid method and silane coupling agent are performed in order to increase the compatibility. It was proved by FE-SEM that no damage was occurred to the carbon nanotube. The addition of carbon nanotube has increased the tensile strength as much as 10.03%, 4.75%, and 7.75% and flexural strength as much as 51.64%, 65.8%, dan 105.9% each for addition of 0.1%, 0.5%, and 1% weight carbon nanotube.

Abstrak :
ABSTRAK
Pada penelitian ini komposit karbon dibuat dengan menggunakan coal tar pitch sebagai prekursor matriks dan serbuk arang batok kelapa (ABK) serta batubara (BB) berukuran 250 mesh sebagai partikel penguat. Jumlah coal tar pitch yang digunakan adalah 30% dari massa total komposit. Untuk mengetahui pengaruh perbandingan massa BB:ABK terhadap densitas, porositas, kekerasan dan keausan, sampel komposit karbon dibuat dengan tiga perbandingan massa BB:ABK yaitu 60:40, 70:30, dan 80:20. Pencetakan dilakukan dengan mesin press hidrolik menggunakan beban 11 U.S. ton pada temperature 100 oC dengan waktu tahan 30 menit. Bakalan hasil kompaksi selanjutnya dikarbonisasi dalam sebuah dapur vakum sederhana pada temperatur 500 oC dengan waktu tahan 15 menit. Hasil pengujian menunjukkan bahwa sifat-sifat komposit karbon seperti densitas, porositas, kekerasan dan keausan terutama dipengaruhi oleh karakteristik partikel penguat yang digunakan. Densitas meningkat dengan peningkatan kandungan batubara, sedangkan porositas mengalami penurunan. Densitas tertinggi diperoleh pada komposit dengan perbandingan massa BB:ABK 80:20, yaitu 1,55 gr/cm3. Porositas terendah diperoleh pada komposit dengan perbandingan massa BB:ABK 80:20, yaitu 31,33%. Kekerasan tertinggi tertinggi dan laju keausan terendah diperoleh pada komposit dengan perbandingan massa BB:ABk 60:40, secara berurutan yaitu 56.44 BHN dan 0.06 mm3/Nm.

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ABSTRACT
Carbon composites were prepared with coal tar pitch as matrix precursor and two granular carbons namely coal waste powder (BB) and coconut shell charcoal powder (ABK) size 250 mesh as reinforcements. The amount of coal tar pitch used was 30 wt. % based on the total mass of the composites. Composites were prepared with three mass ratio BB:ABK , 60:40, 70:30, and 80:20, in order to obtained the influence of mass ratio of BB:ABK to the properties of the carbon composites such as density, porosity, hardness, and wear. The moulding of the mixture was performed in a uniaxial press using 11 U.S ton load at 100 oC for 30 minutes. The green compacts obtained from moulding process were carbonized at 500 o C in a vacuum furnace for 15 minutes. Testing results showed that the properties of the carbon composites mainly governed by the characteristics of the granular carbons that used as reinforcement. Density of the carbon composites increase with the increasing of coal powder content, while the porosity decrease. The highest density was obtained for composites with a mass ratio of 80:20, with density value 1,55 gr/cm3. The lowest porosity was also obtained for composites with a mass ratio of 80:20, with porosity value 31,33 %. The highest hardness value and the lowest wear rate were obtained from composites with a mass ratio 60:40, with hardness and wear rate value 56,44 BHN and 0,06 mm3/Nm, respectively.