Outer layer material for composite roll for rolling and composite roll for rolling

Patent metadata

Field	Value
Publication number	US-10376937-B2
Application number	US-201515500283-A
Country	US
Kind code	B2
Filing date	Aug 6, 2015
Priority date	Aug 25, 2014
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

The present invention provides an outer layer material for a composite roll for rolling, in which the strength of secondary eutectic carbides can be increased by reducing a B amount in the secondary eutectic carbides and surface roughening resistance can be improved, and a composite roll for rolling in which this outer layer material is used in an outer layer. The outer layer material for a composite roll for rolling of the present invention is an outer layer material for a composite roll for rolling containing C in an amount of 1.8 mass % or more and 2.5 mass % or less, Si in an amount of more than 0 mass % and 1.0 mass % or less, Mn in an amount of more than 0 mass % and 1.0 mass % or less, Ni in an amount of more than 0 mass % and 0.5 mass % or less, Cr in an amount of more than 3.0 mass % and 8.0 mass % or less, Mo in an amount of more than 2.0 mass % and 10.0 mass % or less, W in an amount of more than 0 mass % and 10.0 mass % or less, V in an amount of more than 0 mass % and 10.0 mass % or less, and B in an amount of more than 0 mass % and less than 0.01 mass %, and a remaining portion including Fe and inevitable impurities.

First claim

The invention claimed is:

1. An outer layer material for a composite roll for rolling, comprising:
C in an amount of 1.8 mass % or more and 2.5 mass % or less, Si in an amount of more than 0 mass % and 1.0 mass % or less, Mn in an amount of more than 0 mass % and 1.0 mass % or less, Ni in an amount of more than 0 mass % and 0.5 mass % or less, Cr in an amount of more than 3.0 mass % and 8.0 mass % or less, Mo in an amount of 4.0 mass % or more and 10.0 mass % or less, W in an amount of more than 0 mass % and 2.0 mass % or less, V in an amount of more than 0 mass % and 10.0 mass % or less, and B in an amount of more than 0 mass % and less than 0.01 mass %, and a remaining portion including Fe and inevitable impurities;
the outer layer comprising an outer part wherein a mass % of B is B(t1) and an inner part wherein a mass % of B is B(t2), and B(t2)−B(t1)≥0.002.

2. The outer layer material for a composite roll for rolling according to claim 1 , wherein
Mo in an amount of 4.19 mass % or more and 6.3 mass % or less, Win an amount of 0.43 mass % or more and 1.7 mass % or less.

3. The outer layer material for a composite roll for rolling according to claim 2 , further comprising
Nb in an amount of 0.01 mass % or more and 2.0 mass % or less, and/or Ti in an amount of 0.01 mass % or more and 1.0 mass % or less.

4. The outer layer material for a composite roll for rolling according to claim 1 , further comprising
Nb in an amount of 0.01 mass % or more and 2.0 mass % or less, and/or Ti in an amount of 0.01 mass % or more and 1.0 mass % or less.

5. The outer layer material for a composite roll for rolling according to claim 1 , wherein
the outer layer material contains a secondary eutectic carbide, and a melting temperature of the secondary eutectic carbide is higher than 1100° C.

6. The outer layer material for a composite roll for rolling according to claim 1 , wherein
an area percentage of MC carbides of the surface of the outer layer material is 7% to 15%.

7. The outer layer material for a composite roll for rolling according to claim 1 , wherein
an area percentage of secondary eutectic carbides of the surface of the outer layer material is 1% to 6%.

8. A composite roll for rolling, wherein
the outer layer material according to claim 1 is used in an outer layer, and an inner core, or an intermediate layer and an inner core are comprised on an inner side of the outer layer material.

Assignees

• Kubota Kk

Inventors

• Tsujimoto Yutaka
• Odan Tsuyoshi
• Kimura Hiroyuki

Classifications

• C21D1/613

  Gases; Liquefied or solidified normally gaseous material · CPC title

• C22C38/04

  containing manganese · CPC title

• B22D13/00

  Centrifugal casting; Casting by using centrifugal force · CPC title

• C22C37/08

  with nickel · CPC title

• C22C38/56

  with more than 1.7% by weight of carbon · CPC title