Steel

Abstract

A steel according to one aspect of the present invention contains, in unit mass %, C: 0.10% to 0.25%, Si: 0.60% to 1.20%, Mn: 0.60% to 1.00%, P: 0.040% to 0.060%, S: 0.060% to 0.100%, Cr: 0.05% to 0.20%, Bi: 0.0001% to 0.0050%, N: 0.0020% to 0.0150%, V: 0% to 0.010%, Al: 0% to 0.0050%, Ti: 0% to 0.020%, Ca: 0% to 0.005%, Zr: 0% to 0.005%, Mg: 0% to 0.005%, and a remainder including Fe and impurities.

1 . A steel comprising, in unit mass %:
 C: 0.10% to 0.25%;   Si: 0.60% to 1.20%;   Mn: 0.60% to 1.00%;   P: 0.040% to 0.060%;   S: 0.060% to 0.100%;   Cr: 0.05% to 0.20%;   Bi: 0.0001% to 0.0050%;   N: 0.0020% to 0.0150%;   V: 0% to 0.010%;   Al: 0% to 0.0050%;   Ti: 0% to 0.020%;   Ca: 0% to 0.0050%;   Zr: 0% to 0.0050%;   Mg: 0% to 0.0050%; and   a remainder including Fe and impurities.   
     
     
         2 . The steel according to  claim 1  comprising, in unit mass %:
 one or more of:
 Ca: 0.0005% to 0.0050%; 
 Zr: 0.0005% to 0.0050%; and 
 Mg: 0.0005% to 0.0050%. 
 
 
     
     
         3 . The steel according to  claim 1  comprising, in unit mass %:
 N: 0.0020% to 0.0090%. 
 
     
     
         4 . The steel according to  claim 1  comprising, in unit mass %:
 Al: 0% to 0.0008%. 
 
     
     
         5 . The steel according to  claim 1  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         6 . The steel according to  claim 2  comprising, in unit mass %:
 N: 0.0020% to 0.0090%. 
 
     
     
         7 . The steel according to  claim 2  comprising, in unit mass %:
 Al: 0% to 0.0008%. 
 
     
     
         8 . The steel according to  claim 3  comprising, in unit mass %:
 Al: 0% to 0.0008%. 
 
     
     
         9 . The steel according to  claim 6  comprising, in unit mass %:
 Al: 0% to 0.0008%. 
 
     
     
         10 . The steel according to  claim 2  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         11 . The steel according to  claim 3  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         12 . The steel according to  claim 4  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         13 . The steel according to  claim 6  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         14 . The steel according to  claim 7  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         15 . The steel according to  claim 8  comprising, in unit mass %:
 V: 0% to 0.004%. 
 
     
     
         16 . The steel according to  claim 9  comprising, in unit mass %:
 V: 0% to 0.004%.