MATERIAL FOR TRILAMINAR STAINLESS STEEL CLAD STEEL SHEET, PROCESS FOR PRODUCING THICK SHEET OR STEEL SHEET FOR SOLID POLYMER TYPE FUEL CELL SEPARATOR, AND SOLID POLYMER TYPE FUEL CELL SEPARATOR

• Main Authors: SEKI, AKIRA, KANBE, MOTOMICHI, USHIO, KUNIHIKO, YAZAWA, TAKEO, YAMAMOTO, HIDEAKI, TARUTANI, YOSHIO
• Format: Patent
• Language: English; French; German
• Published: 26.08.2009
• Subjects: ALLOYS; CHEMISTRY; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; FERROUS OR NON-FERROUS ALLOYS; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; METALLURGY; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WELDING; WORKING BY LASER BEAM

Provided is a first method for producing a source blank for a clad steel sheet composed of a stainless steel containing 0 to 0.3% B as a core component and a stainless steel containing 0.3 to 2.5% B as face components, the face components each being combined with each of major faces of the core component through the following steps and the like: Step 1: disposing, on side end faces of each face component, protectors with a length greater than a length of the side end faces, disposing tabs each in abutting relation with an extension of the protector's face to abut on the side end face of the face component, and performing bonding between the tabs and the protectors and between the face component and the protectors; Step 2: each composite, which is obtained by removing the tabs and extended portions of the protectors bonded with the tabs from the workpiece after Step 1, is piled on either major face of the core component to thereby obtain a combined block; and Step 3: performing bonding at boundary regions on peripheral four side end faces of the combined block. Further, there is provided a second method for producing a stainless steel three-ply clad sheet for a fuel cell separator, comprising heating the source blank produced by the first method and then performing rough rolling, hot rolling and cold rolling thereto, whereby the clad steel sheet for the fuel cell separator or a solid polymer type fuel cell separator thereby is obtained.. According to this, a source blank for a stainless steel three-ply clad sheet and a separator steel sheet, including B-containing steel as a face layer, which are most suitably used as a solid polymer type fuel cell separator can be provided.