摘要:
The present invention is: a metallic foil to be used for a metallic honeycomb for purifying exhaust gas of an automobile or the like, said metallic foil not causing cracks or ruptures to develop in the foil even when it undergoes corrugation work with more sharply bending corner portions of a trapezoidal shape; and a catalyst support for purifying exhaust gas of an automobile or the like, characterized in that said metallic foil, being rough surface finished and having good corrugation workability, is made of heat-resistant stainless steel and has surface roughness more than 2.0 and not more than 5.0 &mgr;m in Rmax and, said metallic catalyst support for purifying exhaust gas has a structure comprising a honeycomb inserted in a jacket, wherein the honeycomb is composed of rough surface finished metallic foil having surface roughness more than 2.0 and not more than 5.0 &mgr;m in Rmax and the jacket is made of heat-resistant stainless steel.
摘要:
A metallic carrier composed of an end face portion formed in at least one of the axial end portions of a honeycomb body and an outer circumferential reinforcing layer in which foils in a range from the outermost layer to a quarter of the total number of layers are joined together in the axial intermediate portion. Thus, the metallic carrier is flexible in expansion and shrinkage. Further, the honeycomb body and a jacket are joined to each other mainly at the outer circumference of the outer circumferential reinforcing layer of the honeycomb body, to reduce thermal stress developed between the honeycomb body and jacket while maintaining the strength against a high temperature, to thereby prevent the metallic carrier from being ruptured.
摘要:
A method for producing a metallic substrate used for an automobile exhaust gas purifying device, which comprises the steps of: preparing a heat-resisting steel member having a length and capable of containing therein other members; densely filling the heat-resisting steel member with easy-soluble material members and with stainless steel members for separating the easy-soluble material members from each other, to form a filled body; hot-working the filled body to reduce the cross sectional area thereof for achieving a metallic bond between the stainless steel members; cutting the filled body to a predetermined length; and removing the easy-soluble material from the filled body by a chemical and/or an electrochemical treatment for boring throughholes to expose catalyst carrier-destined surfaces of the stainless steel.
摘要:
A metallic carrier for automobile exhaust gas purification made of thin metal foil includes a honeycomb unit composed of 8-25 &mgr;m thick corrugated metal foil and flat metal foil joined by solder joints not fewer than 70% of which have a thickness of at least 1.5 times and not greater than 4 times the foil thickness. A method of producing the metal carrier includes a step of forming a honeycomb unit in which 8-25 &mgr;m thick corrugated metal foil and flat metal foil are joined by solder joints using a solder powder, the solder powder having a particle diameter not greater than 4.5 times the thickness of the metal foil constituting the honeycomb unit.
摘要:
According to the present invention, a strength of 120 to 200 kgf/mm.sup.2 in terms of 0.2% yield point and optionally a spring critical value of 55 to 150 kgf/mm.sup.2 are imparted to a high-strength stainless steel foil for corrugation by subjecting a thin sheet of a stainless steel comprising an alloy composed mainly of 10 to 40% by weight of Cr and 1 to 10% by weight of Al to final cold rolling and optionally subjecting the cold-rolled sheet to an aging treatment at a temperature in the range of from 80.degree. to 500.degree. C. after the completion of the final cold rolling. This enables corrugation to be effected at a high corrugation rate of 10 m/min or more.
摘要:
A method of diametrically contracting a cylindrical body, includes the steps of grasping the cylindrical body with a plurality of elongated grasping members, preparing a cylindrical drawing die having an opening at one end and a tapered inside peripheral surface, drawing the grasping members together with the cylindrical body into the drawing die, through the opening, and applying a compression force to the cylindrical body through the grasping members due to the passage along through the tapered inside peripheral surface, to thereby cause the cylindrical body to be diametrically contracted. During the drawing process, since the cylindrical body does not come into direct contact with the drawing die, neither scratches nor baking cracks are produced on the outside surface of the cylindrical body.
摘要:
An exhaust gas purifying catalyst of this invention comprises a heat resistance stainless steel catalyst support, an oxide film containing zirconium oxide formed on the heat resistance stainless steel catalyst support, an activated alumina catalyst carrier layer formed on the oxide film, and at least one metal catalyst loaded in the activated alumina catalyst carrier layer. Thus, the activated alumina catalyst carrier layer's come-off from the catalyst support and the oxidation of the catalyst support are suppressed at the same time, and the conversions of the hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) are also improved.
摘要:
A rolled high Al stainless steel foil for use as a substrate for a catalyst carrier, which comprises more than 12 wt % up to 20 wt % of Al, from 5 to 25 wt % of Cr, from 0.05 to 2 wt %, in total, of at least one element selected from the group consisting of Ti, Nb, Zr, and Hf, and the remainder substantially consisting of Fe and unavoidable elements. The stainless steel foil has an excellent resistance to oxidation in an engine exhaust gas at a temperature of 1150.degree. C. or higher, can be obtained by foil-rolling, and enables a reduction of the exhaust back-pressure and weight of automobile catalyst converters.
摘要:
In a carrier for a catalyst for purifying exhaust gas, a honeycomb is formed by coiling a corrugated sheet and a flat sheet together, and is mounted in an outer cylinder. An Al (alloy)-clad foil or hot-dip Al (alloy) galvanized foil is used to form the honeycomb, which is heat treated in a vacuum or a reducing atmosphere to simultaneously bond the corrugated sheet and flat sheet together and also bond the honeycomb to the outer cylinder, and to diffuse Al into the foil.
摘要:
In order to improve solid phase diffusion bondability at contact portions between a metal flat foil and a metal corrugated foil together constituting a metal honeycomb body for a catalyst converter used for purifying an exhaust gas and to improve engine durability, the present invention comprises one or combination of the following structures; a structure wherein at least one of the metal foils has a foil thickness of less than 40 &mgr;m; a structure wherein an Al content after bonding is at least 3%; a structure wherein the surface condition of both metal foils in a width-wise direction has a predetermined surface coarseness or a predetermined surface shape and condition; and a structure wherein the width of contact portions between both metal foils is at least five times the thickness of the metal foils. In order to further improve engine durability, the present invention disposes an unbonded portion inside the honeycomb body having the construction described above, or disposes a shell on the outer periphery of the honeycomb body.