The permeability of a new investment casting mold system prepared by adding needle cokes has been
investigated in this work. The permeability tests of the molds were carried out at the temperature of 25—1 200 ?C.
The results showed that the addition of needle cork could significally increase the permeability of the molds by a
factor of about 4 because the burning of needle cokes increased the porosities of the molds. Meanwhile, the needle
coke modified molds exhibited higher green strength and greater thickness both on flat section and at sharp edges
compared with the full fused silica mold. Taking account of the mold thickness, the needle coke modified molds
had increased adjusted fracture load (AFL) by a factor of about 2 at the test temperature of 25—1 200
?C. The addition of needle coke significally improved the permeability of the molds during both autoclaving and casting,
and optimized the correlation between the permeability and green strength of the molds.
WANG Fei (王飞), ZHU Guoliang (祝国梁), LI Fei (李飞), SUN Baode (孙宝德)
. Effect of Needle Coke on Gas Permeability of Ceramic Casting Molds[J]. Journal of Shanghai Jiaotong University(Science), 2018
, 23(Sup. 1)
: 124
-131
.
DOI: 10.1007/s12204-018-2032-8
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