Low-temperature fabrication of porous SiC ceramics by preceramic polymer reaction bonding

Polycarbosilane (PCS) and SiC powders, in which PCS acted as binder, were adopted as starting materials to fabricate porous SiC ceramics. During pyrolysis, PCS experienced an organicinorganic transformation and bonded SiC powders at a low temperature of 1273K. The flexural strength of porous SiC ceramics increased with increasing PCS content and shaping pressure, while the porosity decreased with increasing the PCS content, shaping pressure and particle size of SiC powders. The fracture surface of porous SiC ceramics was observed.

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Fabrication of mullite-bonded porous SiC ceramics via a sol–gel assisted in situ reaction bonding

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2013.08.028 ◽

2014 ◽

Vol 34 (2) ◽

pp. 237-247 ◽

Cited By ~ 43

Author(s):

Omid Ebrahimpour ◽

Charles Dubois ◽

Jamal Chaouki

Keyword(s):

Sol Gel ◽

Reaction Bonding ◽

In Situ Reaction ◽

Sic Ceramics ◽

Porous Sic

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Fabrication, Structure and Properties of Porous SiC Ceramics with High Porosity and High Strength

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.105-106.608 ◽

2010 ◽

Vol 105-106 ◽

pp. 608-611 ◽

Cited By ~ 3

Author(s):

Shao Feng Wang ◽

Chang An Wang ◽

Jia Lin Sun ◽

Li Zhong Zhou ◽

Yong Huang

Keyword(s):

Compressive Strength ◽

High Strength ◽

Butyl Alcohol ◽

Solid Loading ◽

High Porosity ◽

Reaction Bonding ◽

Sintering Additive ◽

Sic Ceramics ◽

Tert Butyl Alcohol ◽

Porous Sic

Porous SiC ceramics with high porosity and high strength were fabricated by gelcasting, with tert-butyl alcohol (TBA) as solvent, acrylamide (AM) as monomer, and in-situ reaction bonding with a-Al2O3 as sintering additive. SiC suspension with 10 vol% solid loading was successfully solidified by gel-casting to form high strength green body. The results showed that the compressive strength of the porous SiC ceramics increased with sintering temperature from 1300 to 1450°C, but porosity had little change, due to formation of more volume of cristobalite and mullite phases on the surface of SiC grains, accompanied by a large volume expansion effect. Very narrow single-peak distributions with about 2 mm median pore diameter could be found for the porous SiC ceramics. The porosity and compressive strength of the porous SiC ceramics sintered at 1450°C were 71.21 % and 12.14 MPa, respectively.

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Effect of Al(OH)3 Addition on the Properties of SiC/Al2O3 Composite Porous Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.1208 ◽

2013 ◽

Vol 821-822 ◽

pp. 1208-1212

Author(s):

Cheng Ying Bai ◽

Zhang Min Liu ◽

Ya Ni Jing ◽

Xiang Yun Deng ◽

Jian Bao Li ◽

...

Keyword(s):

Phase Composition ◽

High Temperature ◽

Mechanical Strength ◽

Porous Ceramics ◽

Reaction Bonding ◽

Sic Ceramics ◽

Porous Sic ◽

Bonding Characteristics ◽

Bonding Technique

SiC/Al2O3composite porous ceramics were prepared by an in situ reaction bonding technique and sintering in air with SiC and A1(OH)3as starting materials. The pores in the ceramics were formed by stacking particles of SiC and A12O3. The surface of SiC was oxidized to SiO2at high temperature. With further increasing the temperature, SiO2reacted with A12O3to form mullite. The reaction bonding characteristics, phase composition, and mechanical strength as well as microstructure of porous SiC ceramics were investigated.

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