Hot working die steel for die-casting

Abstract

The invention provides a hot-working die steel for die-casting obtainable by quenching a steel comprising, in terms of % by mass, C: 0.1 to 0.3%, Si: 0.1 to 1.5%, Mn: 0.3 to 2%, Cr: 6 to 12%, P: 0.05% or less, S: 0.01% or less, Mo: 1 to 3%, V: 0.5 to 1.5%, s-Al: 0.005 to 0.025%, N: 0.005 to 0.025%, and O: 0.005% or less, with the remainder being Fe and inevitable impurities, followed by tempering the steel at a temperature of 500° C. or lower.

1 . A hot-working die steel for die-casting obtainable by quenching a steel comprising, in terms of % by mass,
 C: 0.1 to 0.3%,   Si: 0.1 to 1.5%,   Mn: 0.3 to 2%,   Cr: 6 to 12%,   P: 0.05% or less,   S: 0.01% or less,   Mo: 1 to 3%,   V: 0.5 to 1.5%,   s-Al: 0.005 to 0.025%,   N: 0.005 to 0.025%, and   O: 0.005% or less,   with the remainder being Fe and   inevitable impurities,   
       followed by tempering the steel at a temperature of 500° C. or lower. 
     
     
         2 . The hot-working die steel for die-casting according to  claim 1 , which further comprises at least one member selected from the group consisting of, in terms of % by mass,
 Ni: 2% or less, and   Cu: 1% or less.   
     
     
         3 . The hot-working die steel for die-casting according to  claim 1 , which further comprises, in terms of % by mass,
 Co: 5% or less.   
     
     
         4 . The hot-working die steel for die-casting according to  claim 2 , which further comprises, in terms of % by mass,
 Co: 5% or less.   
     
     
         5 . The hot-working die steel for die-casting according to  claim 1 , which further comprises at least one member selected from the group consisting of, in terms of % by mass,
 Ti: 0.2% or less,   Zr: 0.2% or less, and   Nb: 0.2% or less.   
     
     
         6 . The hot-working die steel for die-casting according to  claim 2 , which further comprises at least one member selected from the group consisting of, in terms of % by mass,
 Ti: 0.2% or less,   Zr: 0.2% or less, and   Nb: 0.2% or less.   
     
     
         7 . The hot-working die steel for die-casting according to  claim 3 , which further comprises at least one member selected from the group consisting of, in terms of % by mass,
 Ti: 0.2% or less,   Zr: 0.2% or less, and   Nb: 0.2% or less.   
     
     
         8 . The hot-working die steel for die-casting according to  claim 4 , which further comprises at least one member selected from the group consisting of, in terms of % by mass,
 Ti: 0.2% or less,   Zr: 0.2% or less, and   Nb: 0.2% or less.