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Direct coagulation casting of silicon carbide suspension via polyelectrolyte dispersant crosslink reaction
Author(s) -
Gan Ke,
Gai Yanjiao,
Wang Yali,
Cui Jie,
Lu Yuju,
Zhang Xiaoyan,
Liu Jingjing,
Xu Jie,
Yang Jinlong
Publication year - 2019
Publication title -
international journal of applied ceramic technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.4
H-Index - 57
eISSN - 1744-7402
pISSN - 1546-542X
DOI - 10.1111/ijac.13328
Subject(s) - dispersant , materials science , silicon carbide , suspension (topology) , carboxymethyl cellulose , ceramic , chemical engineering , composite material , coagulation , silicon , sintering , relative density , casting , metallurgy , dispersion (optics) , psychology , physics , mathematics , homotopy , psychiatry , pure mathematics , optics , engineering , sodium
A direct coagulation casting method for silicon carbide ceramic suspension using dispersant crosslink reaction is reported. Polymer electrolyte (polyethyleneimine, PEI) was used as dispersant to prepare silicon carbide suspension. Common food additives (carboxymethyl cellulose, CMC) were used to coagulate the electrosteric stabilized silicon carbide suspension. There was a well disperse silicon carbide suspension with 0.2 wt% PEI at pH = 5‐6. Influence of coagulant on viscosity and zeta potential of the silicon carbide suspension was investigated. It indicates that the high solid loading silicon carbide suspension can be destabilized and coagulated at elevated temperature. It can be attribute to the gradual decrease of electrosteric force due to the crosslink reaction between PEI and CMC. Silicon carbide wet green body with compressive strength of 1.99 MPa could be demolded at 70°C which is higher than that prepared by traditional DCC and dispersant reaction method for nonoxide ceramics. Dense silicon carbide ceramics with relative density above 98.8% and 99.3% had been prepared by liquid phase pressureless and hot pressed sintering, respectively.