Stock cold-rolled steel sheet with fe-based coating film, method for producing stock cold-rolled steel sheet with fe-based coating film, method for producing cold-rolled steel sheet with fe-based coating film, method for producing hot-dipped galvanized steel sheet, and method for producing alloyed hot-dipped galvanized steel sheet

Abstract

There is provided a raw material cold-rolled steel sheet with Fe-based coating film excellent in primary rust prevention property or plating appearance. The raw material cold-rolled steel sheet with Fe-based coating film comprises: a base steel sheet having a chemical composition containing C of 0.80 mass % or less, Si of 0.10 mass % or more and 3.00 mass % or less, Mn of 1.50 mass % or more and 3.50 mass % or less, P of 0.100 masse or less; S of 0.0300 mass % or less, Al of 0.100 mass % or less, with a remaining part consisting of Fe and inevitable impurities; and a P-adhered Fe-based coating film containing an Fe-based coating film disposed on at least one surface of the base steel sheet and a P-containing substance adhered to a surface of the Fe-based coating film, and an adhesion amount of the P-containing substance in terms of P is 0.2 mg/m 2 or more.

1 . A raw material cold-rolled steel sheet with Fe-based coating film comprising:
 a base steel sheet having a chemical composition containing,   C in an amount of 0.80 mass % or less,   Si in an amount of 0.10 mass % or more and 3.00 mass % or less,   Mn in an amount of 1.50 mass % or more and 3.50 mass % or less,   P in an amount of 0.100 mass % or less;   S in an amount of 0.0300 mass % or less,   Al in an amount of 0.100 mass % or less,   N in an amount of 0.0100 mass % or less,   B in an amount of 0.0050 mass % or less,   Ti in an amount of 0.200 mass % or less,   with a remaining part consisting of Fe and inevitable impurities; and   a P-adhered Fe-based coating film comprising an Fe-based coating film disposed on at least one surface of the base steel sheet and a P-containing substance adhered to a surface of the Fe-based coating film,   wherein an adhesion amount of the P-containing substance in terms of P is 0.2 mg/m 2  or more.   
     
     
         2 . The raw material cold-rolled steel sheet with Fe-based coating film according to  claim 1 , wherein a coating amount of the Fe-based coating film per one surface of the base steel sheet is 1.0 g/m 2  or more. 
     
     
         3 . The raw material cold-rolled steel sheet with Fe-based coating film according to  claim 2 , wherein the chemical composition further contains at least one element selected from the group consisting of:
 Cr in an amount of 1.000 mass % or less,   Mo in an amount of 1.000 mass % or less,   Cu in an amount of 1.000 mass % or less,   Ni in an amount of 1.000 mass % or less,   Nb in an amount of 0.200 mass % or less,   V in an amount of 0.500 mass % or less,   Sb in an amount of 0.200 mass % or less,   Ta in an amount of 0.100 mass % or less,   W in an amount of 0.500 mass % or less,   Zr in an amount of 0.1000 mass % or less,   Sn in an amount of 0.200 mass % or less,   Ca in an amount of 0.0050 mass % or less,   Mg in an amount of 0.0050 mass % or less, and   REM in an amount of 0.0050 mass % or less.   
     
     
         4 . The raw material cold-rolled steel sheet with Fe-based coating film according to  claim 2 , wherein the Fe-based coating film has a chemical composition containing at least one element selected from the group consisting of B, C, P, N, O, Ni, Mn, Mo, Zn, W, Pb, Sn, Cr, V, and Co in a total amount of 10 mass % or less, with a remaining part consisting of Fe and inevitable impurities. 
     
     
         5 . A method for producing a raw material cold-rolled steel sheet with Fe-based coating film, the method comprising:
 subjecting a base steel sheet having a chemical composition containing C in an amount of 0.80 mass % or less, Si in an amount of 0.10 mass % or more and 3.00 mass % or less, Mn in an amount of 1.50 mass % or more and 3.50 mass % or less, P in an amount of 0.100 mass % or less, S in an amount of 0.0300 mass % or less, Al in an amount of 0.100 mass % or less, N in an amount of 0.0100 mass % or less, B in an amount of 0.0050 mass % or less, Ti in an amount of 0.200 mass % or less, with a remaining part consisting of Fe and inevitable impurities to an Fe-based electroplating treatment to form an Fe-based coating film on at least one surface of the base steel sheet; and   bringing a surface of the Fe-based coating film into contact with an alkaline aqueous solution for 0.5 seconds or more followed by rinsing the surface of the Fe-based coating film with water and drying, wherein   the alkaline aqueous solution contains P-containing ions, and   a content of the P-containing ions in the alkaline aqueous solution is 0.01 g/L or more in terms of P.   
     
     
         6 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 5 , wherein the alkaline aqueous solution contains at least one phosphorus compound selected from the group consisting of a phosphate, a pyrophosphate, and a triphosphate. 
     
     
         7 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 5 , wherein pH of the alkaline aqueous solution is 8 or more. 
     
     
         8 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 5 , wherein the chemical composition further contains at least one element selected from the group consisting of:
 Cr in an amount of 1.000 mass % or less,   Mo in an amount of 1.000 mass % or less,   Cu in an amount of 1.000 mass % or less,   Ni in an amount of 1.000 mass % or less,   Nb in an amount of 0.200 mass % or less,   V in an amount of 0.500 mass % or less,   Sb in an amount of 0.200 mass % or less,   Ta in an amount of 0.100 mass % or less,   W in an amount of 0.500 mass % or less,   Zr in an amount of 0.1000 mass % or less,   Sn in an amount of 0.200 mass % or less,   Ca in an amount of 0.0050 mass % or less,   Mg in an amount of 0.0050 mass % or less, and   REM in an amount of 0.0050 mass % or less.   
     
     
         9 . A method for producing a cold-rolled steel sheet with Fe-based coating film, the method comprising subjecting the raw material cold-rolled steel sheet with Fe-based coating film according to  claim 1  to an annealing treatment to obtain the cold-rolled steel sheet with Fe-based coating film. 
     
     
         10 . A method for producing a hot-dip galvanized steel sheet, the method comprising subjecting the cold-rolled steel sheet with Fe-based coating film obtained by the method according to  claim 9  to a hot-dip galvanizing treatment to obtain the hot-dip galvanized steel sheet. 
     
     
         11 . A method for producing an alloyed hot-dip galvanized steel sheet, the method comprising subjecting the hot-dip galvanized steel sheet obtained by the method according to  claim 10  to an alloying treatment to obtain the alloyed hot-dip galvanized steel sheet. 
     
     
         12 . The raw material cold-rolled steel sheet with Fe-based coating film according to  claim 2 , wherein the Fe-based coating film has a chemical composition containing at least one element selected from the group consisting of B, C, P, N, O, Ni, Mn, Mo, Zn, W, Pb, Sn, Cr, V, and Co in a total amount of 10 mass % or less, with a remaining part consisting of Fe and inevitable impurities. 
     
     
         13 . The raw material cold-rolled steel sheet with Fe-based coating film according to  claim 3 , wherein the Fe-based coating film has a chemical composition containing at least one element selected from the group consisting of B, C, P, N, O, Ni, Mn, Mo, Zn, W, Pb, Sn, Cr, V, and Co in a total amount of 10 mass % or less, with a remaining part consisting of Fe and inevitable impurities. 
     
     
         14 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 6 , wherein pH of the alkaline aqueous solution is 8 or more. 
     
     
         15 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 6 , wherein the chemical composition further contains at least one element selected from the group consisting of:
 Cr in an amount of 1.000 mass % or less,   Mo in an amount of 1.000 mass % or less,   Cu in an amount of 1.000 mass % or less,   Ni in an amount of 1.000 mass % or less,   Nb in an amount of 0.200 mass % or less,   V in an amount of 0.500 mass % or less,   Sb in an amount of 0.200 mass % or less,   Ta in an amount of 0.100 mass % or less,   W in an amount of 0.500 mass % or less,   Zr in an amount of 0.1000 mass % or less,   Sn in an amount of 0.200 mass % or less,   Ca in an amount of 0.0050 mass % or less,   Mg in an amount of 0.0050 mass % or less, and   REM in an amount of 0.0050 mass % or less.   
     
     
         16 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 7 , wherein the chemical composition further contains at least one element selected from the group consisting of:
 Cr in an amount of 1.000 mass % or less,   Mo in an amount of 1.000 mass % or less,   Cu in an amount of 1.000 mass % or less,   Ni in an amount of 1.000 mass % or less,   Nb in an amount of 0.200 mass % or less,   V in an amount of 0.500 mass % or less,   Sb in an amount of 0.200 mass % or less,   Ta in an amount of 0.100 mass % or less,   W in an amount of 0.500 mass % or less,   Zr in an amount of 0.1000 mass % or less,   Sn in an amount of 0.200 mass % or less,   Ca in an amount of 0.0050 mass % or less,   Mg in an amount of 0.0050 mass % or less, and   REM in an amount of 0.0050 mass % or less.   
     
     
         17 . The method for producing a raw material cold-rolled steel sheet with Fe-based coating film according to  claim 14 , wherein the chemical composition further contains at least one element selected from the group consisting of:
 Cr in an amount of 1.000 mass % or less,   Mo in an amount of 1.000 mass % or less,   Cu in an amount of 1.000 mass % or less,   Ni in an amount of 1.000 mass % or less,   Nb in an amount of 0.200 mass % or less,   V in an amount of 0.500 mass % or less,   Sb in an amount of 0.200 mass % or less,   Ta in an amount of 0.100 mass % or less,   W in an amount of 0.500 mass % or less,   Zr in an amount of 0.1000 mass % or less,   Sn in an amount of 0.200 mass % or less,   Ca in an amount of 0.0050 mass % or less,   Mg in an amount of 0.0050 mass % or less, and   REM in an amount of 0.0050 mass % or less.   
     
     
         18 . A method for producing a cold-rolled steel sheet with Fe-based coating film, the method comprising subjecting the raw material cold-rolled steel sheet with Fe-based coating film according to  claim 3  to an annealing treatment to obtain the cold-rolled steel sheet with Fe-based coating film. 
     
     
         19 . A method for producing a hot-dip galvanized steel sheet, the method comprising subjecting the cold-rolled steel sheet with Fe-based coating film obtained by the method according to  claim 18  to a hot-dip galvanizing treatment to obtain the hot-dip galvanized steel sheet. 
     
     
         20 . A method for producing an alloyed hot-dip galvanized steel sheet, the method comprising subjecting the hot-dip galvanized steel sheet obtained by the method according to  claim 19  to an alloying treatment to obtain the alloyed hot-dip galvanized steel sheet.