FERRITIC STAINLESS STEEL FOR EXHAUST SYSTEM MEMBER HAVING EXCELLENT CORROSION RESISTANCE AFTER HEATING

• Main Authors: URASHIMA HIROSHI, HIRAIDE NOBUHIKO
• Format: Patent
• Language: English; Korean
• Published: 07.08.2019
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

가열 후 내식성이 우수한 배기계 부재용 페라이트계 스테인리스강을 제공한다. 질량％로, C: 0.015％ 이하, N: 0.02％ 이하, Si: 0.03 내지 1.0％, Mn: 1.0％ 이하, P: 0.04％ 이하, S: 0.01％ 이하, Cr: 10.5 내지 22.5％, Sn: 0.02 내지 0.5％, Al: 0.003 내지 0.2％를 함유하고, 또한, Ti: 0.03 내지 0.35％ 및 Nb: 0.03 내지 0.6％의 1종 또는 2종을 함유하고, 잔부가 Fe 및 불가피적 불순물로 이루어지고, 표면의 결정립도 번호가 6 이상이고, 또한 모재 농도의 2배 이상의 Sn을 포함하는 층이 2 내지 15㎚ 형성되어 있는 것을 특징으로 하는 가열 후 내식성이 우수한 배기계 부재용 페라이트계 스테인리스강. A ferritic stainless steel for exhaust system components excellent in corrosion resistance after heating is provided. A ferritic stainless steel for exhaust system components excellent in corrosion resistance after heating includes: 0.015 mass% or less of C; 0.02 mass% or less of N; 0.03 mass% to 1.0 mass of Si; 1.0 mass of Mn; 0.04 mass of P; 0.01 mass of S; 10.5 mass% to 22.5 mass of Cr; 0.02 mass% to 0.5 mass of Sn; 0.003 mass% to 0.2 mass of Al; one or both of 0.03 mass% to 0.35 mass of Ti and 0.03 mass% to 0.6 mass of Nb; and a remnant comprising Fe and inevitable impurities, wherein a grain size number on a surface of the ferritic stainless steel is 6 to 2 to 15 nm of a layer containing Sn at a concentration twice or more of Sn content in the base material is formed on the ferritic stainless steel.