Abstract A honeycomb structure as a substrate for a catalyst has at least one partially melted surface on an outer surface of the structure. A roughness of the melted surface is coarser than other surfaces. With the coarse surface, shifting of the honeycomb structure in through-aperture directions and rotation about its axis are prevented, thereby enhancing the reliability of a catalyst converter incorporating the honeycomb structure therein. A method of producing the honeycomb structure includes steps of, after extruding a ceramic batch into a honeycomb structure, drying the extruded honeycomb structure, attaching a chemical compound having a low melting point at a predetermined position onto an outer wall surface of the dried honeycomb structure, and firing the structure to melt at least a part of the outer wall surface, thereby obtaining the honeycomb structure having a melted portion whose roughness is coarser than the other surfaces of the outer wall.
A cylindrical ceramic honeycomb structure comprising an outer surface wall surrounding and encompassing a plurality of partition walls and through-holes, at least one portion of said outer surface having a coarser surface roughness than a remaining portion of said outer surface resulting from partial melting of said at least one portion of said outer surface.
Claim 2
Dependent Claim
55 words
A cylindrical ceramic honeycomb structure comprising an outer surface wall surrounding and encompassing a plurality of partition walls and through-holes, at least one portion of said outer surface having a coarser surface roughness than a remaining portion of said outer surface resulting from partial melting of said at least one portion of said outer surface.
Claim 3
Dependent Claim
38 words
The honeycomb structure of claim 1, wherein said honeycomb structure is cylindrical and said at least one portion extends circumferentially around said honeycomb structure at a position located substantially axially midway between opposite ends of said honeycomb structure.
Claim 4
Dependent Claim
18 words
The honeycomb structure of claim 2, wherein said at least one portion extends entirely around said honeycomb structure.
Claim 5
Dependent Claim
32 words
A catalyst converter comprising the honeycomb structure of claim 1 arranged in a converter can and a ceramic mat arranged between said honeycomb structure and an inner surface of said converter can.