The Webb Law Firm
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
Provided is 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, remainder Fe, and other unavoidable impurities, having a microstructure formed of ferrite and pearlite, and in which a prior (before cooling) austenite grain size is 8 μm or less.
Posco
C C C C C C C C
C22C C22C C22C C22C C22C C21D C22C C21D
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Jeong Do Yong Tae Jae Seung Hoe Young Byoung Ju Duk Lak Jay Hyung Sang Woo
Seo Shin Lee Jung Park Lee Jung Choi