Steel wire rod for high strength and high toughness spring having excellent cold workability, method for producing the same and method for producing spring by using the same

• Main Authors: SEO JEONG-DO, SHIN YONG-TAE, JUNG HOE-YOUNG, JUNG JAY-HYUNG, LEE JAE-SEUNG, CHOI SANG-WOO, LEE DUK-LAK, PARK BYOUNG-JU
• Format: Patent
• Language: Chinese; English
• Published: 02.03.2011
• Subjects: ALLOYS; CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; TREATMENT OF ALLOYS OR NON-FERROUS METALS

The invention provides a steel wire rod for a high strength and high toughness spring having excellent cold workability, the steel wire rod having a composition comprising: in weight %, C: 0.4 to 0.7%The invention provides a steel wire rod for a high strength and high toughness spring having excellent cold workability, the steel wire rod having a composition comprising: in weight %, C: 0.4 to 0.7%, Si: 1.5 to 3.5%, Mn: 0.3 to 1.0%, Cr: 0.01 to 1.5%, Ni: 0.01 to 1.0%, Cu: 0.01 to 1.0%, B:0.005 to 0.02%, Al:0.1% or less, O: 0,0020% or less, P: 0.02% or less, S: 0.02% or less, N:0.02% or less, re, Si: 1.5 to 3.5%, Mn: 0.3 to 1.0%, Cr: 0.01 to 1.5%, Ni: 0.01 to 1.0%, Cu: 0.01 to 1.0%, B:0.005 to 0.02%, Al:0.1% or less, O: 0,0020% or less, P: 0.02% or less, S: 0.02% or less, N:0.02% or less, remainder Fe, and other unavoidable impurities, having an internal structure formed of ferrite and pearlite, the internal structure in which prior austenite grain size is 8 [mu]m or less.mainder Fe, and other unavoidable impur