Steel for storage equipment and transportation equipment for ethanol (as amended)

Abstract

Steel for storage equipment and transportation equipment for ethanol, the steel having a chemical composition containing, by mass %. C: 0.02% to 0.3%, Si: 0.01% to 1.0%, Mn: 0.1% to 2.0%, P: 0.003% to 0.03%, S: 0.01% or less, Al: 0.005% to 0.100%, N: 0.0010% to 0.010%, at least one selected from W: 0.010% to 0.5% and Mo: 0.010% to 0.5%, at least one selected from Sb: 0.01% to 0.5% and Sn: 0.01% to 0.3%, and the balance being Fe and inevitable impurities, in which the ratio of the Al content to the N content satisfies the relationship 2.0≤Al/N≤70.0.

1 . Steel for storage equipment and transportation equipment for ethanol, the steel having a chemical composition containing, by mass %,
 C: 0.02% to 0.3%,   Si: 0.01% to 1.0%,   Mn: 0.1% to 2.0%,   P: 0.003% to 0.03%,   S: 0.01% or less,   Al: 0.005% to 0.100%,   N: 0.0010% to 0.010%,   at least one selected from W: 0.010% to 0.5% and Mo: 0.010% to 0.5%,   at least one selected from Sb: 0.01% to 0.5% and Sn: 0.01% to 0.3%, and   the balance being Fe and inevitable impurities, in which the ratio of the Al content to the N content satisfies the relationship 2.0≤Al/N≤70.0.   
     
     
         2 . The steel for storage equipment and transportation equipment for ethanol according to  claim 1 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Cu: 0.05% to 1.0%,   Cr: 0.01% to 1.0%, and   Ni: 0.01% to 1.0%.   
     
     
         3 . The steel for storage equipment and transportation equipment for ethanol according to  claim 1 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Ca: 0.0001% to 0.02%,   Mg: 0.0001% to 0.02%, and   REM: 0.001% to 0.2%.   
     
     
         4 . The steel for storage equipment and transportation equipment for ethanol according to  claim 1 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Ti: 0.005% to 0.1%,   Zr: 0.005% to 0.1%,   Nb: 0.005% to 0.1%, and   V: 0.005% to 0.1%.   
     
     
         5 . The steel for storage equipment and transportation equipment for ethanol according to  claim 1 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         6 . The steel for storage equipment and transportation equipment for ethanol according to  claim 2 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Ca: 0.0001% to 0.02%,   Mg: 0.0001% to 0.02%, and   REM: 0.001% to 0.2%.   
     
     
         7 . The steel for storage equipment and transportation equipment for ethanol according to  claim 2 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Ti: 0.005% to 0.1%,   Zr: 0.005% to 0.1%,   Nb: 0.005% to 0.1%, and   V: 0.005% to 0.1%.   
     
     
         8 . The steel for storage equipment and transportation equipment for ethanol according to  claim 3 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Ti: 0.005% to 0.1%,   Zr: 0.005% to 0.1%,   Nb: 0.005% to 0.1%, and   V: 0.005% to 0.1%.   
     
     
         9 . The steel for storage equipment and transportation equipment for ethanol according to  claim 6 , wherein the steel has the chemical composition further containing, by mass %, at least one selected from
 Ti: 0.005% to 0.1%,   Zr: 0.005% to 0.1%,   Nb: 0.005% to 0.1%, and   V: 0.005% to 0.1%.   
     
     
         10 . The steel for storage equipment and transportation equipment for ethanol according to  claim 2 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         11 . The steel for storage equipment and transportation equipment for ethanol according to  claim 3 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         12 . The steel for storage equipment and transportation equipment for ethanol according to  claim 4 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         13 . The steel for storage equipment and transportation equipment for ethanol according to  claim 6 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         14 . The steel for storage equipment and transportation equipment for ethanol according to  claim 7 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         15 . The steel for storage equipment and transportation equipment for ethanol according to  claim 8 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less. 
     
     
         16 . The steel for storage equipment and transportation equipment for ethanol according to  claim 9 , wherein the steel further has a tensile strength of 825 MPa or less and a yield strength of 705 MPa or less.