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conferenceseries
.com
Volume 6
Research & Reviews: Journal of Material Sciences
ISSN: 2321-6212
Ceramics 2018
May 14-15, 2018
May 14-15, 2018 | Rome, Italy
4
th
International Conference and Expo on
Ceramics and Composite Materials
Joining and machining of (ZrB
2
-SiC) and (Cf-SiC) based composites
R. V. Krishnarao, G. Madhusudan reddy
and
V.V.Bhanuprasad
Defence Metallurgical Research Laboratory, India
Z
rB
2
-SiC and Cf-SiC based ultra high temperature ceramics (UHTC) are most promising materials for the application
in thermal protection systems and high temperature components of future hypersonic aircraft or reentry vehicles. The
difficulty in fabricating large size or complex shapes limits the application of these composites. Machining and joining are
inevitable requirement for flexible use of advanced ceramics. Diamond machining is an expensive and time consuming
process. Low cost near net shape processing of ceramic parts with complex geometries is possible with pressure less sintering
(PS). (ZrB
2
-SiC-B
4
C-YAG) composites have been developed by PS of (ZrB
2
-SiC-B
4
C) with (Y
2
O
3
-Al
2
O
3
) sintering additives at
relatively low temperature of 1550-1680
o
C. Filler materials of (ZrB
2
-SiC-B
4
C-YAG) composite were developed for tungsten
inert gas (TIG) welding of the ZrB
2
-SiC and Cf-SiC based composites to themselves and to each other. By incorporation of Cf-
SiC short fibre reinforcement the (ZrB
2
-SiC-B
4
C-YAG) composites were machinable with tungsten carbide tool bit. The joint
and machined composite exhibited resistance to oxidation and thermal shock upon exposure to oxy-propane flame at 2300
o
C
for 300 seconds. The combination of (ZrB
2
-SiC-B
4
C-YAG) and Cf-SiC based composites can be used for making low cost parts
like thermal protection system or nozzles for rocket motors.
rvkr4534@yahoo.comRes. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C1-015