Railway wheel

Patent metadata

Field	Value
Publication number	US-12049102-B2
Application number	US-201917276510-A
Country	US
Kind code	B2
Filing date	Sep 27, 2019
Priority date	Sep 28, 2018
Publication date	Jul 30, 2024
Grant date	Jul 30, 2024

Abstract

Provided is a railway wheel which has excellent toughness even if the C content is as high as 0.80% or more. The chemical composition of the railway wheel of the present embodiment consists of: in mass %, C: 0.80 to 1.60%, Si: 1.00% or less, Mn: 0.10 to 1.25%, P: 0.050% or less, S: 0.030% or less, Al: 0.010 to 0.650%, and N: 0.0030 to 0.0200%, with the balance being Fe and impurities, and wherein, in a microstructure of the web part of the railway wheel, an area fraction of pearlite is 85.0% or more, an area fraction of pro-eutectoid cementite is 0.90 to 15.00%, and an average value of a width W of the pro-eutectoid cementite defined by Formula (3) is less than 0.70 μm:

W =½×( P /2−(( P /2) 2 −4 A ) 1/2 )  (3)
where, in Formula (3), A is an area (μm 2 ) of the pro-eutectoid cementite, and P is a circumference length (μm) of the pro-eutectoid cementite.

First claim

The invention claimed is:

1. A railway wheel, comprising:
a rim part,
a hub part, and
a web part which is disposed between the rim part and the hub part and is linked to the rim part and the hub part, wherein
a chemical composition of the railway wheel consists of: in mass %,
C: 0.80 to 1.60%,
Si: 1.00% or less,
Mn: 0.10 to 1.25%,
P: 0.050% or less,
S: 0.030% or less,
Al: 0.010 to 0.650%,
N: 0.0030 to 0.0200%,
Cr: 0 to 0.60%, and
V: 0 to 0.12%, with
the balance being Fe and impurities, and wherein
in a microstructure of the web part of the railway wheel, an area fraction of pearlite is 85.0% or more, an area fraction of pro-eutectoid cementite is 0.90 to 15.00%, and an average value of a width W of the pro-eutectoid cementite defined by Formula (3) is 0.95 μm or less:
W= ½×( P/ 2−(( P/ 2) 2 −4 A ) 1/2 )  (3)

where, A in Formula (3) is an area (μm 2 ) of the pro-eutectoid cementite, and P is a circumference length (μm) of the pro-eutectoid cementite.

2. The railway wheel according to claim 1 , wherein in a microstructure of the hub part of the railway wheel, an area fraction of pearlite is 85.0% or more, an area fraction of the pro-eutectoid cementite is 0.90 to 15.00%, and an average value of a width W of the pro-eutectoid cementite defined by Formula (3) is 0.95 μm or less.

3. The railway wheel according to claim 2 , wherein the chemical composition contains one or more elements selected from the group consisting of:
Cr: 0.02 to 0.60%, and
V: 0.02 to 0.12%.

4. The railway wheel according to claim 1 , wherein the chemical composition contains one or more elements selected from the group consisting of:
Cr: 0.02 to 0.60%, and
V: 0.02 to 0.12%.

5. A railway wheel comprising:
a rim part,
a hub part, and
a web part which is disposed between the rim part and the hub part and is linked to the rim part and the hub part, wherein
a chemical composition of the railway wheel consists of, in mass %,
C: 0.80 to 1.60%,
Si: 1.00% or less,
Mn: 0.10 to 1.25%,
P: 0.050% or less,
S: 0.030% or less,
Al: 0.010 to 0.650%,
N: 0.0030 to 0.0200%,
Cr: 0 to 0.60%, and
V: 0 to 0.12%, with
the balance being Fe and impurities, and wherein
in a microstructure of the web part of the railway wheel, an area fraction of pearlite is 85.0% or more, an area fraction of pro-eutectoid cementite is 0.90 to 15.00%, and a maximum width of the pro-eutectoid cementite is 1.80 μm or less.

6. The railway wheel according to claim 5 , wherein
in a microstructure of the hub part of the railway wheel, an area fraction of pearlite is 85.0% or more, an area fraction of the pro-eutectoid cementite is 0.90 to 15.00%, and a maximum width of the pro-eutectoid cementite is 1.80 μm or less.

7. The railway wheel according to claim 6 , wherein the chemical composition contains one or more elements selected from the group consisting of:
Cr: 0.02 to 0.60%, and
V: 0.02 to 0.12%.

8. The railway wheel according to claim 5 , wherein the chemical composition contains one or more elements selected from the group consisting of:
Cr: 0.02 to 0.60%, and
V: 0.02 to 0.12%.

Assignees

• Nippon Steel Corp

Inventors

• Maejima Taketo
• Kubota Manabu

Classifications

• C22C38/24

  with vanadium · CPC title

• C22C38/06

  containing aluminium · CPC title

• C22C38/04

  containing manganese · CPC title

• C22C38/02 Primary

  containing silicon · CPC title

• C22C38/002

  containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60 · CPC title