Method for brazing heat resisting alloy having on its surface insulating oxide film and preheat type metallic carrier for purification of exhaust gas and process for producing the same
US5618498A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jan 12, 1995 |
| Grant date | Apr 8, 1997 |
| Priority date | — |
| Expiry date | Jan 12, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24149
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The present invention aims to produce a metallic carrier which enables a catalyst to be activated in a short time. In mutually joining an insulated heat resisting alloy and a heat resisting alloy having an insulating film, particularly composed mainly of alumina, a joining material of a laminate, formed by laminating a strongly reducing metal, which can thermodynamically reduce alumina, and a brazing material to each other, is disposed so that the strongly reducing metal comes into contact with the insulated heat resisting alloy, and the resultant laminate is heated in a non-oxidizing atmosphere to carry out a brazing treatment. This enables only portions in the honeycomb structure, where electrically conductive paths are to be formed, can be joined, and, at the same time, heat resisting alloys having a surface covered with an insulating oxide film can be firmly joined with the resultant joint having an electrical conductivity. The above joining method can be utilized to provide a preheat type metallic carrier having an excellent conversion efficiency, wherein only a surface layer portion on the side of an inlet for an exhaust gas can be heated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.