Sintered ceramic filter structure having body compressively stressed by sintered ceramic material having different sintering shrinkage ratio

摘要

A sintered ceramic structure for cleaning noxious substances contained in the exhaust gases emitted by an internal combustion engine is disclosed. The stucture comprises: an exhaust-gas cleaning portion including a multiplicity of pores through which the exhaust gas is discharged and an exhaust-gas inlet portion and an exhaust-gas outlet portion; an external wall portion being integrally disposed around the outer periphery of the exhaust-gas cleaning portion except for both the exhaust-gas inlet portion and the exhaust-gas outlet portion of the exhaust-gas cleaning portion; the exhaust-gas cleaning portion and the external wall portion being constituted by ceramics; and the ceramics of the external wall portion being composed of a sintered ceramic material having a sintering-shrinkage ratio smaller than that of the ceramics of the sintered ceramic material of the noxious gas cleaning portion, whereby upon sintering a residual compressive stress is imparted to the external wall portion due to the difference between the sintered-shrinkage ratios.