Effect of Needle Coke on Gas Permeability of Ceramic Casting Molds

doi:10.1007/s12204-018-2032-8

Abstract

Abstract: 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.

Key words: permeability, mold, needle coke, strength, investment casting

摘要： 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.

关键词: permeability, mold, needle coke, strength, investment casting

CLC Number:

TB 321

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 Jiao Tong University (Science), 2018, 23(Sup. 1): 124-131.

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