Hot stamped steel

Abstract

A hot stamped steel according to one embodiment of the present invention includes a base material and a plated layer, wherein the plated layer includes an interface layer, an intermediate layer, and an oxide layer in order from a base material side to a surface side; in which compositions and thicknesses of each layer are controlled.

1 . A hot stamped steel comprising:
 a base material; and   a plated layer,   wherein the plated layer includes an interface layer, an intermediate layer, and an oxide layer in order from a base material side to a surface side,   in the interface layer, a structure includes 99 area % or more in total of αFe, Fe 3 Al, and FeAl, an average Al content is in a range of 8.0 mass % or more and 32.5 mass % or less, an average Zn content is limited to more than a Zn content of the base material and 5 mass % or less, a remainder of a chemical composition includes Fe and impurities, and an average layer thickness is 1.0 μm or more,   in the intermediate layer, a structure includes 99 area % or more in total of Fe(Al, Zn) 2  and Fe 2 (Al, Zn) 5 , an average Al content is 30 mass % to 50 mass %, an average Zn content is 10 mass % to 40 mass %, a remainder of a chemical composition includes Fe and the impurities, and an average layer thickness is 5.0 μm or more, and   in the oxide layer, an average layer thickness is 0.1 μm to 3.0 μm.   
     
     
         2 . The hot stamped steel according to  claim 1 ,
 wherein the average layer thickness is 1.0 μm to 10.0 μm in the interface layer.   
     
     
         3 . The hot stamped steel according to  claim 1 ,
 wherein a total weight per unit area of Al and Zn in the plated layer is 20 g/m 2  or more and 100 g/m 2  or less.   
     
     
         4 . The hot stamped steel according to  claim 1 ,
 wherein the plated layer further includes more than 0 mass % and 10.0 mass % or less of Si on average, and   in the intermediate layer, 0 area % to 50 area % of the Fe(Al, Zn) 2  and the Fe 2 (Al, Zn) 5  are substituted into Fe(Al, Si).   
     
     
         5 . The hot stamped steel according to  claim 2 ,
 wherein a total weight per unit area of Al and Zn in the plated layer is 20 g/m 2  or more and 100 g/m 2  or less.   
     
     
         6 . The hot stamped steel according to  claim 2 ,
 wherein the plated layer further includes more than 0 mass % and 10.0 mass % or less of Si on average, and   in the intermediate layer, 0 area % to 50 area % of the Fe(Al, Zn) 2  and the Fe 2 (Al, Zn) 5  are substituted into Fe(Al, Si).   
     
     
         7 . The hot stamped steel according to  claim 3 ,
 wherein the plated layer further includes more than 0 mass % and 10.0 mass % or less of Si on average, and   in the intermediate layer, 0 area % to 50 area % of the Fe(Al, Zn) 2  and the Fe 2 (Al, Zn) 5  are substituted into Fe(Al, Si).   
     
     
         8 . The hot stamped steel according to  claim 5 ,
 wherein the plated layer further includes more than 0 mass % and 10.0 mass % or less of Si on average, and   in the intermediate layer, 0 area % to 50 area % of the Fe(Al, Zn) 2  and the Fe 2 (Al, Zn) 5  are substituted into Fe(Al, Si).