STEEL FOR AUTOMOTIVE SUSPENSION SPRING COMPONENT, AUTOMOTIVE SUSPENSION SPRING COMPONENT, AND METHOD FOR MANUFACTURING THE SAME

• Main Authors: TOMITA KUNIKAZU, KIKUCHI KATSUHIKO, HATTORI KAZUAKI, KURIMOTO KIYOSHI, TANGE AKIRA, FUKUOKA KAZUAKI, GOTO YURIKA
• Format: Patent
• Language: English
• Published: 06.12.2012
• Subjects: ALLOYS; BLASTING; CHEMISTRY; ENGINEERING ELEMENTS AND UNITS; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MEANS FOR DAMPING VIBRATION; MECHANICAL ENGINEERING; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SHOCK-ABSORBERS; SPRINGS; THERMAL INSULATION IN GENERAL; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WEAPONS

PROBLEM TO BE SOLVED: To provide steel for an automotive suspension spring component that improves corrosion resistance of the material itself, has high strength, such as tensile strength of at least 1,300 MPa, and has excellent corrosion resistance and low temperature toughness, and to provide an automotive suspension spring component, and a method for manufacturing the same.SOLUTION: The steel for an automotive suspension spring component includes 0.15-0.35 mass% of C, more than 0.6 mass% and not more than 1.5 mass% of Si, 1-3 mass% of Mn, 0.3-0.8 mass% of Cr, 0.005-0.080 mass% of sol. Al, 0.005-0.060 mass% of Ti, 0.005-0.060 mass% of Nb, not more than 150 ppm of N, not more than 0.035 mass% of P, not more than 0.035 mass% of S, 0.01-1.00 mass% of Cu, and 0.01-1.00 mass% of Ni, with the remainder comprising Fe and unavoidable impurities, wherein Ti+Nb≤0.07 mass%, and has excellent corrosion resistance and low temperature toughness with the tensile strength of at least 1,300 MPa.