US4461811A
Expired / Lapsed
US
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Stabilized ferritic stainless steel with improved brazeability
Assignee: Allegheny Ludlum Corp
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Filing: 1982-07-27
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Granted: 1984-07-24
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Expires: 2002-07-27
Abstract
Abstract A stabilized ferritic stainless steel is wettable by brazing materials used at temperatures of from 2000° F. to 2100° F. The steel consists essentially of, by weight, 10.5% to 13.5% chromium, up to 0.1% carbon, up to 0.05% nitrogen, up to about 0.12% titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship: ##EQU1##
Inventors
- 👤 Paul R. Borneman
- 👤 George Aggen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:25
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/26; C22C38/28; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12903; Y10T428/12917; Y10T428/12924
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
70 words
A brazeable ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.05% nitrogen, up to 0.10% aluminum, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element selected from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU3## the steel being wettable by brazing filler materials.
Claim 2
Dependent Claim
70 words
A brazeable ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.05% nitrogen, up to 0.10% aluminum, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element selected from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU3## the steel being wettable by brazing filler materials.
Claim 3
Dependent Claim
81 words
A brazeable ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.050% nitrogen, u to 0.10% aluminum, up to 1.25% molybdenum, up to 1% manganese, up to 1% silicon, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU4## the steel being wettable by brazing filler materials.
Claim 4
Dependent Claim
81 words
A brazeable ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.050% nitrogen, u to 0.10% aluminum, up to 1.25% molybdenum, up to 1% manganese, up to 1% silicon, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU4## the steel being wettable by brazing filler materials.
Claim 5
Dependent Claim
77 words
A brazeable ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.03% nitrogen, up to 0.020% aluminum, up to 1% manganese, up to 1% silicon, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU5## the steel being wettable by brazing filler materials.
Claim 6
Dependent Claim
77 words
A brazeable ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.03% nitrogen, up to 0.020% aluminum, up to 1% manganese, up to 1% silicon, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU5## the steel being wettable by brazing filler materials.
Claim 7
Dependent Claim
22 words
The brazeable ferritic stainless steel of claims 1, 2 or 3 wherein the titanium is present in amounts up to about 0.01%.
Claim 8
Dependent Claim
22 words
The brazeable ferritic stainless steel of claims 1, 2 or 3 wherein the titanium is present in amounts up to about 0.005%.
Claim 9
Dependent Claim
21 words
The ferritic stainless steel of claims 1, 2 or 3 wherein the titanium is present in amounts of at least 0.001%.
Claim 10
Dependent Claim
13 words
The brazeable ferritic steel of claims 1, 2 or 3 stabilized by niobium.
Claim 11
Dependent Claim
13 words
The brazeable ferritic steel of claims 1, 2 or 3 stabilized by tantalum.
Claim 12
Dependent Claim
18 words
The ferritic stainless steel of claims 1, 2 or 3 wherein the steel is wettable by molten copper.
Claim 13
Dependent Claim
29 words
The ferritic stainless steel of claims 1, 2 or 3 wherein the titanium is present in amounts up to about 0.01% and the steel is wettable by molten copper.
Claim 14
Dependent Claim
29 words
The ferritic stainless steel of claims 1, 2 or 3 wherein the titanium is present in amounts up to about 0.005% and the steel is wettable by molten copper.
Claim 15
Dependent Claim
18 words
A brazed ferritic stainless steel article having the composition of the steel of claims 1, 2 or 3.
Claim 16
Dependent Claim
24 words
A ferritic stainless steel article having the composition of the steel of claims 1, 2 or 3 wherein the article is brazed with copper.
Claim 17
Dependent Claim
16 words
The brazeable ferritic steel of claims 1, 2, or 3 stabilized with up to 1.0% niobium.
Claim 18
Dependent Claim
16 words
The brazeable ferritic steel of claims 1, 2, or 3 stabilized with up to 1.8% tantalum.
Claim 19
Independent Claim
83 words
A method of brazing ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.05% nitrogen, up to 0.10% aluminum, up to 1.25% molybdenum, up to 1% manganese, up to 1% silicon, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU6## the steel being brazed with a filler material.
Claim 20
Independent Claim
83 words
A method of brazing ferritic stainless steel consisting essentially of, by weight, 10.5% to 13.5% chromium, up to 0.03% carbon, up to 0.05% nitrogen, up to 0.10% aluminum, up to 1.25% molybdenum, up to 1% manganese, up to 1% silicon, up to about 0.12% titanium, up to 0.12% aluminum plus titanium and at least one other stabilizing element from the group consisting of niobium and tantalum in an amount in accordance with the relationship ##EQU6## the steel being brazed with a filler material.
Claim 21
Dependent Claim
13 words
The method of brazing of claim 16 wherein the filler material is copper.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-24 | 1988-01-23 | 1988-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-24 | 1992-01-23 | 1992-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-24 | 1996-01-23 | 1996-07-24 | $7700.00 | Window Closed / Lapsed |