SILICON NITRIDE POROUS BODY AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a silicon nitride porous body which has a porous structure with a large average pore size and large thermal conductivity and small thermal expansivity of a cut-off test piece, and is preferably used for a gas and/or solution purification part of a ceramic filter or the like. SOLUTION: The silicon nitride porous body is obtained by nitriding a formed body having a metal silicon as a main component and carrying out high temperature heat treatment at a temperature higher than a nitriding temperature, and is characterized by having the porous structure with a average pore size of 3 μm or larger and containing at least one kind of elements selected from the group consisting of II group A and III group A, and III group B and IV group B including a lanthanoid element.