Effects of organic additives on microstructure and mechanical properties of porous Si3N4 ceramics

Bulletin of Materials Science

关键词: Organic additives;    processing;    microstructure;    mechanical properties;    porous Si3N4 ceramics;    Weibull distribution.;   

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Green bodies of porous Si3N4 ceramics were shaped by extrusion technique using different organic additives as binder during extrusion molding. Different porosity, microstructures and mechanical properties after the extrusion, drying, debinding and sintering stages were investigated. The solid slurry content of 70–75% and extrusion pressure of 0.5–1.0 MPa had played a decisive role in the smooth realization of extrusion molding. The porous Si3N4 ceramics were obtained with excellent properties using 4% hydroxypropyl methyl cellulose (HPMC) as binder and polyethylene glycol (PEG) of molecular weight, 1000, as plasticizer with a density of 1.91 g cm-3, porosity of 41.70%, three-point bending strength of 166.53 ± 20 MPa, fracture toughness of 2.45 ± 0.2 MPa m1/2 and Weibull modulus (m) of 20.75.

【 授权许可】

CC BY