FERRITIC STAINLESS STEEL FOR BIOFUEL SUPPLY SYSTEM PARTS, AND BIOFUEL SUPPLY SYSTEM PARTS

• Main Authors: SATSUNOKI TOMIO, SAKAMOTO TOSHIHARU, HIRAIDE NOBUHIKO
• Format: Patent
• Language: English
• Published: 08.11.2012
• Subjects: ALLOYS; BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMBUSTION ENGINES; DIFFUSION TREATMENT OF METALLIC MATERIAL; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MECHANICAL ENGINEERING; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SUPPLYING COMBUSTION ENGINES IN GENERAL, WITH COMBUSTIBLEMIXTURES OR CONSTITUENTS THEREOF; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WEAPONS

PROBLEM TO BE SOLVED: To provide ferritic stainless steel for parts having corrosion resistance to biofuel.SOLUTION: The ferritic stainless steel for biofuel supply system parts contains, by mass, 0.03% or less of C, 0.03% or less of N, more than 0.1% and 1% or less of Si, 0.02% or more and 1.2% or less of Mn, 15% or more and 23% or less of Cr, 0.002% or more and 0.5% or less of Al, and one or both of Nb and Ti, and satisfies the following formulas (1): 8(C+N)+0.03≤Nb+Ti≤0.6 and (2): Si+Cr+Al+[Nb+Ti-8(C+N)]≥15.5 (wherein the symbols of elements show the content (mass%) of the respective elements). The ferritic stainless steel has a remaining portion consisting of Fe and inevitable impurities, and is formed on the surface with an oxide film containing 30% or more of Cr, Si, Nb, Ti and Al in total of cation fraction.