Long life mold tool steel with improved physical properties at high temperature and mold using the same

Abstract

The present invention relates to an alloy steel for a mold tool and a mold using the same. The steel for the mold tool comprises iron (Fe) as a main component, an amount of about 0.35 to 0.45 wt % of carbon (C), amount of about 0.80 to 1.20 wt % of silicon (Si), amount of about 0.20 to 0.50 wt % of manganese (Mn), amount of about 6.00 to 8.00 wt % of chromium (Cr), amount of about 1.50 to 3.00 wt % of molybdenum (Mo), and amount of about 0.80 to 1.20 wt % of vanadium (V) based on the total weight of the tool steel. Accordingly, the mold tool have improved physical properties at high temperature and extended life span.

What is claimed is: 
     
         1 . An alloy steel for a mold tool, comprising:
 amount of about 0.35 to 0.45 wt % of carbon (C),   amount of about 0.80 to 1.20 wt % of silicon (Si),   amount of about 0.20 to 0.50 wt % of manganese (Mn),   amount of about 6.00 to 8.00 wt % of chromium (Cr),   amount of about 1.50 to 3.00 wt % of molybdenum (Mo),   amount of about 0.80 to 1.20 wt % of vanadium (V), and   iron (Fe) constituting the remaining balance of the alloy steel,   all the wt % based on the total weight of the alloy steel.   
     
     
         2 . The alloy steel of  claim 1 , further comprising niobium (Nb). 
     
     
         3 . The alloy steel of  claim 2 , wherein a content of the niobium (Nb) is about 0.05 to 0.10 wt % based on the total weight of the alloy steel. 
     
     
         4 . The alloy steel of  claim 1 , further comprising tungsten (W). 
     
     
         5 . The alloy steel of  claim 4 , wherein a content of the tungsten (W) is amount of about 0.10 to 1.00 wt % based on the total weight of the alloy steel. 
     
     
         6 . The alloy steel of  claim 1 , further comprising niobium (Nb) and tungsten (W). 
     
     
         7 . The alloy steel of  claim 6 , wherein a content of the niobium (Nb) is amount of about 0.05 to 0.10 wt % and a content of the tungsten (W) is amount of about 0.10 to 1.00 wt % based on the total weight of the alloy steel. 
     
     
         8 . The alloy steel of  claim 1 , consisting essentially of:
 amount of about 0.35 to 0.45 wt % of carbon (C),   amount of about 0.80 to 1.20 wt % of silicon (Si),   amount of about 0.20 to 0.50 wt % of manganese (Mn),   amount of about 6.00 to 8.00 wt % of chromium (Cr),   amount of about 1.50 to 3.00 wt % of molybdenum (Mo),   amount of about 0.80 to 1.20 wt % of vanadium (V), and   iron (Fe) constituting the remaining balance of the alloy steel,   all the wt % based on the total weight of the alloy steel.   
     
     
         9 . The alloy steel of  claim 1 , consisting essentially of:
 amount of about 0.35 to 0.45 wt % of carbon (C),   amount of about 0.80 to 1.20 wt % of silicon (Si),   amount of about 0.20 to 0.50 wt % of manganese (Mn),   amount of about 6.00 to 8.00 wt % of chromium (Cr),   amount of about 1.50 to 3.00 wt % of molybdenum (Mo),   amount of about 0.80 to 1.20 wt % of vanadium (V),   amount of about 0.05 to 0.10 wt % of niobium (Nb), and   iron (Fe) constituting the remaining balance of the alloy steel,   all the wt % based on the total weight of the alloy steel.   
     
     
         10 . The alloy steel of  claim 1 , consisting essentially of:
 amount of about 0.35 to 0.45 wt % of carbon (C),   amount of about 0.80 to 1.20 wt % of silicon (Si),   amount of about 0.20 to 0.50 wt % of manganese (Mn),   amount of about 6.00 to 8.00 wt % of chromium (Cr),   amount of about 1.50 to 3.00 wt % of molybdenum (Mo),   amount of about 0.80 to 1.20 wt % of vanadium (V),   amount of about 0.10 to 1.00 wt % of tungsten (W), and   iron (Fe) constituting the remaining balance of the alloy steel,   all the wt % based on the total weight of the alloy steel.   
     
     
         11 . The alloy steel of  claim 1 , consisting essentially of:
 amount of about 0.35 to 0.45 wt % of carbon (C),   amount of about 0.80 to 1.20 wt % of silicon (Si),   amount of about 0.20 to 0.50 wt % of manganese (Mn),   amount of about 6.00 to 8.00 wt % of chromium (Cr),   amount of about 1.50 to 3.00 wt % of molybdenum (Mo),   amount of about 0.80 to 1.20 wt % of vanadium (V),   amount of about 0.05 to 0.10 wt % of niobium (Nb),   amount of about 0.10 to 1.00 wt % of tungsten (W), and   iron (Fe) constituting the remaining balance of the alloy steel,   all the wt % based on the total weight of the alloy steel.   
     
     
         12 . A mold comprising a steel of  claim 1 .