The present invention relates to a rail which has a predetermined chemical composition and in which at least 90% of a metallographic structure from an outer surface of the rail bottom portion, as the origin, to a depth of 5 mm is a pearlite structure, a surface hardness HC of a foot-bottom central portion is in a range of Hv 360 to 500, a surface hardness HE of a foot-edge portion is in a range of Hv 260 to 315, and HC, HE, and a surface hardness HM of a middle portion positioned between the foot-bottom central portion and the foot-edge portion satisfy HC≥HM≥HE.
1. A rail comprising, as steel composition, in terms of mass %:
C: 0.75% to 1.20%;
Si: 0.10% to 2.00%;
Mn: 0.10% to 2.00%;
Cr: 0% to 2.00%;
Mo: 0% to 0.50%;
Co: 0% to 1.00%;
B: 0% to 0.0050%;
Cu: 0% to 1.00%;
Ni: 0% to 1.00%;
V: 0% to 0.50%;
Nb: 0% to 0.050%;
Ti: 0% to 0.0500%;
Mg: 0% to 0.0200%;
Ca: 0% to 0.0200%;
REM: 0% to 0.0500%;
Zr: 0% to 0.0200%;
N: 0% to 0.0200%;
Al: 0% to 1.00%;
P: 0.0250% or less;
S: 0.0250% or less; and
Fe and impurities as a remainder, wherein
90% or more of a metallographic structure in a range between an outer surface of a rail bottom portion as an origin and a depth of 5 mm is a pearlite structure,
an HC which is a surface hardness of a foot-bottom central portion is in a range of Hv 360 to 500,
an HE which is a surface hardness of a foot-edge portion is in a range of Hv 260 to 315, and
the HC, the HE, and an HM which is a surface hardness of a middle portion positioned between the foot-bottom central portion and the foot-edge portion satisfy the following Expression 1,
HC≥HM≥HE (Expression 1).
2. The rail according to claim 1 , wherein the HM and the HC satisfy the following Expression 2,
HM/HC≥0.900 (Expression 2).
3. The rail according to claim 1 ,
wherein the steel composition comprises, in terms of mass %, at least one selected from the group consisting of
Cr: 0.01% to 2.00%,
Mo: 0.01% to 0.50%,
Co: 0.01% to 1.00%,
B: 0.0001% to 0.0050%,
Cu: 0.01% to 1.00%,
Ni: 0.01% to 1.00%,
V: 0.005% to 0.50%,
Nb: 0.0010% to 0.050%,
Ti: 0.0030% to 0.0500%,
Mg: 0.0005% to 0.0200%,
Ca: 0.0005% to 0.0200%,
REM: 0.0005% to 0.0500%,
Zr: 0.0001% to 0.0200%,
N: 0.0060% to 0.0200%, and
Al: 0.0100% to 1.00%.
4. The rail according to claim 2 ,
wherein the steel composition comprises, in terms of mass %, at least one selected from the group consisting of
Cr: 0.01% to 2.00%,
Mo: 0.01% to 0.50%,
Co: 0.01% to 1.00%,
B: 0.0001% to 0.0050%,
Cu: 0.01% to 1.00%,
Ni: 0.01% to 1.00%,
V: 0.005% to 0.50%,
Nb: 0.0010% to 0.050%,
Ti: 0.0030% to 0.0500%,
Mg: 0.0005% to 0.0200%,
Ca: 0.0005% to 0.0200%,
REM: 0.0005% to 0.0500%,
Zr: 0.0001% to 0.0200%,
N: 0.0060% to 0.0200%, and
Al: 0.0100% to 1.00%.