2011 , 4 , No. 29 ,Vol. & Tech. Journal Eng.
* Applied Sciences Department, University of Technology / Baghdad
665
Mechanical Strength of Silicon Carbide Bonded
with Iraqi Clays
Dr. Kassim S. Kassim*, Dr. Shihab Ahmed Zaidan Al- Juboori*
& Dr.Abdul Mutalb Al Sheikh*
Received on: 16 / 5 /2010
Accepted on: 3/2 /2011
Abstract
Two types of Iraqi clays (Kaolin and Bentonite) were used in bonding process
with different weight percentage (5%, 10%, 15%, 20%, and 25%) and with
different particle size from clays and silicon carbide.
The specimens were formed by using low biaxial pressing and two types of
internal lubricants (sodium silicate and the carbon paste) to increase the
specimen's cohesion. These specimens were sintered at various temperatures of
(1100°C, 1200°C, 1300°C, and 1400°C).
Increasing of clay percentage leads to decreasing the porosity. But it leads to
increase mechanical properties (compressive strength, diametrical strength and
bending strength ). Also, the effect of particle size on all properties is studied
together with sintering temperature. All mechanical properties (when bonded SiC
with bentonite) are higher than kaolin bonded SiC.
Keywords: silicon carbide; kaolin; bentonite; compressive strength;
diametrical strength; bending strength
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ا
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15%, 20%, 25% ن ن( ن)( و. واد ن نو ط ر ا$ دم ا
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$ $ رار( ت) در ت دت ا م, وري( س ا دام ا ت ا: 1100°C,
1200°C, 1300°, 1400°C .
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) ط’!2 أ$ , ر ا$ وء(2 ا$ ( ز4 ) د ازدادت5 نط ا$ دة
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Introduction
lay-bonded silicon carbide
has a high thermal
conductivity and low
thermal expansion, which gives it
excellent thermal shock resistance.
Clay-bonded silicon carbide is
composed of roughly 73 to 77%
SiC, 17 to 21% Al2O3, and
4 to 6% SiO2. Silicon carbide
also offers high strength at
elevated temperatures. The
C