High strength wire rod having non-magnetic property and method for manufacturing thereof

Abstract

The present invention relates to a wire rod used as a material for a core wire for a power line and, more specifically, to a wire rod having both high strength and a non-magnetic property, and a method for manufacturing same.

1 . A non-magnetic high-strength wire rod comprising, by weight: 27 to 42% of manganese (Mn), 0.35% or less (excluding 0%) of carbon (C), 0.5% or less of silicon (Si), 0.03% or less of phosphorus (P) , and 0.03% or less of sulfur (S) , with a balance of Fe and other unavoidable impurities,
 wherein the wire rod has a Néel temperature of higher than 150° C.   
     
     
         2 . The non-magnetic high-strength wire rod of  claim 1 , further comprising: 3.5% or less of niobium (Nb). 
     
     
         3 . The non-magnetic high-strength wire rod of  claim 1 , wherein the wire rod includes an austenite single phase structure as a microstructure. 
     
     
         4 . The non-magnetic high-strength wire rod of  claim 1 , wherein the wire rod has a coefficient of thermal expansion at room temperature of 10×10 −6 /° C. or less. 
     
     
         5 . The non-magnetic high-strength wire rod of  claim 1 , wherein the wire rod has a relative magnetic permeability of 1.05μ or less. 
     
     
         6 . A method for manufacturing a non-magnetic high-strength wire rod, the method comprising:
 preparing a steel piece or an ingot including, by weight: 27 to 42% of manganese (Mn), 0.35% or less (excluding 0%) of carbon (C), 0.5% or less of silicon (Si), 0.03% or less of phosphorus (P), and 0.03% or less of sulfur (S), with a balance of Fe and other unavoidable impurities,   heat treating the steel piece or the ingot in a temperature range of 1000 to 1250° C. to manufacture a billet, and   subjecting the billet to wire rod rolling in a temperature range of 800 to 1250° C. to manufacture a wire rod,   wherein the wire rod has a Néel temperature of higher than 150° C.   
     
     
         7 . The method for manufacturing a non-magnetic high-strength wire rod of  claim 6 , wherein the steel piece or the ingot further includes 3.5% or less of niobium (Nb).