METHOD FOR REDUCING TARGET SURFACE FEATURES IN CONTINUOUS CASTING

• US 20190321880A1
• Filed: 04/24/2018
• Published: 10/24/2019
• Est. Priority Date: 04/24/2018
• Status: Active Grant

• Current Assignee: Golden Aluminum, Inc.
• Original Assignee: Golden Aluminum, Inc.
• Inventors: Selepack, Mark
• Granted Patent: US 11,130,171 B2
• Time in Patent Office: Days
• CPC Class Codes: B22D 11/003 Aluminium alloys
• CPC Class Codes: B22D 11/0605 formed by two belts, e.g. Hazelett-process
• CPC Class Codes: B22D 11/0622 formed by two casting wheels
• CPC Class Codes: B22D 11/126 for cutting

Abstract

A method for reducing target surface features in continuously cast articles is described. The method can remove a target surface feature, such as a compositional variation or casting defect, from the continuously cast article by removing, before cold rolling, material from the continuously cast article surface.

Claims

1. A method, comprising:

providing a continuously cast article having a first target surface feature on a first surface of the continuously cast article; and

before cold rolling, removing material from the first surface of the continuously cast article by abrasion to provide a treated article, wherein a dimension of the first target surface feature on the first surface of the treated article is less than a corresponding dimension of the first target surface feature on the first surface of the continuously cast article.

2. The method of claim 1, wherein, during the removing step, the continuously cast article has a temperature of at least about 700 degrees Fahrenheit, wherein the continuously cast article is a strip, wherein the cast article comprises primarily aluminum, wherein the cast article is continuously cast by one or more of a rotary caster, a twin-roll caster, a block caster, a twin-belt caster, and a single roll caster, and wherein the target surface feature is substantially removed from the first surface in the treating step.

3. The method of claim 1, wherein the first target surface feature is a compositional deviation, wherein the cast article is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, wherein, in the removing step, at least about 10 microns of material is removed from the first surface, and wherein at least most of the first target surface feature is removed from the first surface during the removing step.

4. The method of claim 2, wherein the first target surface feature is one or more of a step, ramp, bow, buckle, streak, drag mark, and block joint, wherein at least most of the first target surface feature is removed from the first surface during the removing step, wherein, in the removing step, at least about 50 microns of material is removed from the first surface, and wherein the removing step is performed before hot rolling.

5. The method of claim 1, wherein the first target surface feature comprises an oxidized surface, wherein the continuously cast article is a strip or sheet, wherein, during the removing step, the continuously cast article has a temperature of at least about 500 degrees Fahrenheit, wherein at least most of the first target surface feature is removed from the first surface during the removing step, and wherein the removing step is performed between hot rolling stands.

6. The method of claim 1, wherein, in the removing step, the continuously cast article is a strip or sheet, wherein at least about 50 microns of material is removed from the first surface, wherein at least most of the first target surface feature is removed from the first surface during the removing step, and wherein the removing step is performed after hot rolling is completed.

7. The method of claim 6, wherein the cast article is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, and wherein, during the removing step, the continuously cast article has a temperature of at least about 400 degrees Fahrenheit.

8. The method of claim 1, wherein the cast article is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, and wherein at least about 25% of the first target surface feature is removed during the removing step.

24. The method of claim 1, wherein the cast article is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX and wherein at least about 25% of the first target surface feature is removed during the removing step.

9. A method, comprising:

continuously casting an alloy to form a strip having a target surface feature on a first surface of the continuously cast strip; and

before cold rolling, reducing, by abrasion, a thickness of the target surface feature while maintaining a substantially constant width of the continuously cast strip derived therefrom to provide a treated strip, wherein the target surface feature is substantially removed from the first surface during the reducing step.

10. The method of claim 9, wherein, during the removing step, the continuously cast strip has a temperature of at least about 700 degrees Fahrenheit, wherein the cast strip comprises primarily aluminum, wherein the cast strip is continuously cast by one or more of a rotary caster, a twin-roll caster, a block caster, a twin-belt caster, and a single roll caster, and wherein the target surface feature is substantially removed from the first surface in the treating step.

11. The method of claim 9, wherein the first target surface feature is a compositional variation, wherein the cast strip is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, wherein at least about 10 microns of material is removed from the first surface, and wherein at least most of the first target surface feature is removed from the first surface during the removing step.

12. The method of claim 10, wherein the first target surface feature is one or more of a step, ramp, bow, buckle, streak, drag mark, and block joint, wherein at least most of the first target surface feature is removed from the first surface during the removing step, wherein, in the reducing step, at least about 50 microns of material is removed from the first surface, and wherein the reducing step is performed before hot rolling.

13. The method of claim 9, wherein the first target surface feature comprises an oxidized surface, wherein, during the reducing step, the continuously cast strip has a temperature of at least about 700 degrees Fahrenheit, wherein at least most of the first target surface feature is removed from the first surface during the reducing step, and wherein the removing step is performed between hot rolling stands.

14. The method of claim 9, wherein, in the reducing step, at least about 50 microns of material is removed from the first surface, wherein at least most of the first target surface feature is removed from the first surface during the reducing step, and wherein the reducing step is performed after hot rolling is completed.

15. The method of claim 14, wherein the cast strip is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, and wherein, during the reducing step, the continuously cast strip has a temperature of at least about 400 degrees Fahrenheit.

16. The method of claim 9, wherein the cast strip is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, and wherein at least about 25% of the first target surface feature is removed during the reducing step.

17. A method, comprising:

providing a continuously cast article having a first target surface feature on a first surface of the continuously cast article; and

while the continuously cast article has a temperature of at least about 70 degrees Fahrenheit, removing, by abrasion, material from the first surface.

18. The method of claim 17, wherein the first target surface feature is substantially removed from the first surface during the removing step, wherein, during the removing step, the continuously cast article has a temperature of at least about 700 degrees Fahrenheit, wherein the continuously cast article is a strip, wherein the cast article comprises primarily aluminum, and wherein the cast article is continuously cast by one or more of a rotary caster, a twin-roll caster, a block caster, a twin-belt caster, and a single roll caster.

19. The method of claim 17, wherein the first target surface feature is a compositional deviation, wherein the cast article is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, wherein, in the removing step, at least about 10 microns of material is removed from the first surface, and wherein at least most of the first target surface feature is removed from the first surface during the removing step.

20. The method of claim 18, wherein the first target surface feature is one or more of a step, ramp, bow, buckle, streak, drag mark, and block joint, wherein at least most of the first target surface feature is removed from the first surface during the removing step, wherein, in the removing step, at least about 50 microns of material is removed from the first surface, and wherein the removing step is performed before hot rolling.

21. The method of claim 17, wherein the continuously cast article is a strip or sheet, wherein, during the removing step, the continuously cast article has a temperature of at least about 700 degrees Fahrenheit, wherein at least most of the first target surface feature is removed from the first surface during the removing step, and wherein the removing step is performed between hot rolling stands.

22. The method of claim 17, wherein the continuously cast article is a strip or sheet, wherein, in the removing step, at least about 50 microns of material is removed from the first surface, wherein at least most of the first target surface feature is removed from the first surface during the removing step, and wherein the removing step is performed after hot rolling is completed.

23. The method of claim 22, wherein the cast article is an aluminum alloy selected from the group consisting of aluminum alloys 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, 7XXX, 8XXX, and 9XXX, and wherein, during the removing step, the continuously cast article has a temperature of at least about 400 degrees Fahrenheit.