Patent US3980444A successfully refreshed from Google Patents.
US3980444A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sintered liquid phase stainless steel
Assignee: Allegheny Ludlum Corp
•
Filing: 1975-01-22
•
Granted: 1976-09-14
•
Expires: 1995-01-22
Abstract
Abstract A sintered stainless steel having an overall density of at least 95% of full density and a morphology comprised of regions of sintered austenitic stainless steel and regions of solidified liquid phase. Moreover, a sintered steel which is made by: pressing and sintering pre-alloyed powder consisting essentially of, by weight, up to 0.05% carbon, 22 to 26% chromium, 10 to 24% nickel, 2.7 to 5% molybdenum, 0.1 to 1% boron, up to 2.0% manganese, up to 2.0% silicon, balance iron and residuals.
Inventors
- 👤 Orville W. Reen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:04
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/40; C22C38/54; C22C33/00; C22C33/02; C22C33/0257; C22C33/0278; C22C33/0285; Y; Y10; Y10S; Y10S75/00; Y10S75/95
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
102 words
A sintered stainless steel having excellent resistance to corrosive attack by the chloride ion; said steel having an overall composition consisting essentially of, by weight, up to 0.05% carbon, 22 to 26% chromium, 10 to 24% nickel, 2.7 to 5% molybdenum, 0.1 to 1% boron, up to 2.0% manganese, up to 2.0% silicon, balance iron and residuals, said steel having a morphology comprised of regions of sintered austenitic stainless steel and regions of solidified liquid phase; said steel having an overall density of at least 95% of full density; said morphology being comprised of from 8 to 25% of said liquid phase.
Claim 2
Dependent Claim
102 words
A sintered stainless steel having excellent resistance to corrosive attack by the chloride ion; said steel having an overall composition consisting essentially of, by weight, up to 0.05% carbon, 22 to 26% chromium, 10 to 24% nickel, 2.7 to 5% molybdenum, 0.1 to 1% boron, up to 2.0% manganese, up to 2.0% silicon, balance iron and residuals, said steel having a morphology comprised of regions of sintered austenitic stainless steel and regions of solidified liquid phase; said steel having an overall density of at least 95% of full density; said morphology being comprised of from 8 to 25% of said liquid phase.
Claim 3
Dependent Claim
20 words
A sintered stainless steel according to claim 1, having from 22.3 to 26% chromium and from 3 to 5% molybdenum.
Claim 4
Dependent Claim
14 words
A sintered stainless steel according to claim 1, having from 0.2 to 0.5% boron.
Claim 5
Dependent Claim
30 words
A sintered stainless steel according to claim 1, having from 22.3 to 26% chromium, from 13 to 18% nickel, from 3 to 5% molybdenum and from 0.2 to 0.5% boron.
Claim 6
Dependent Claim
19 words
A sintered stainless steel according to claim 1, having an overall density of at least 98% of full density.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-14 | 1980-03-15 | 1980-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-14 | 1984-03-15 | 1984-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-14 | 1988-03-15 | 1988-09-14 | $7700.00 | Window Closed / Lapsed |