US4004922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Free machining steel
Assignee: Ugine Aciers SA
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Filing: 1975-09-03
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Granted: 1977-01-25
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Expires: 1995-09-03
Abstract
Abstract Free machining low alloy steel compositions are prepared by addition of very small quantities of at least magnesium to previously deoxidized steel to provide a homogeneous distribution of globular sulfides and sulfurous inclusions of the additive.
Inventors
- 👤 Daniel Thivellier
- 👤 Leon Seraphin
- 👤 Roland Tricot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:51
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/60
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
78 words
A previously deoxidized, resulfurated free machining steel, having a homogeneous distribution of globular sulfides and sulfurous inclusions and having a sulfur content of about 0.04 and about 0.5% and having a greatly improved crosswise ductility and resilience, characterized in that it contains sulfur globularizing free magnesium in a quantity at the most equal to 0.005% and at the least equal to 5 thousandths of the sulfur content, said magnesium having been added to said steel subsequent to deoxidation.
Claim 2
Dependent Claim
78 words
A previously deoxidized, resulfurated free machining steel, having a homogeneous distribution of globular sulfides and sulfurous inclusions and having a sulfur content of about 0.04 and about 0.5% and having a greatly improved crosswise ductility and resilience, characterized in that it contains sulfur globularizing free magnesium in a quantity at the most equal to 0.005% and at the least equal to 5 thousandths of the sulfur content, said magnesium having been added to said steel subsequent to deoxidation.
Claim 3
Dependent Claim
25 words
A steel according to claim 1, characterised in that it contains in addition to magnesium one at lest of the elements Ca, Ba and Sr.
Claim 4
Dependent Claim
22 words
A steel according to claim 2, characterised in that the total content of calcium, barium, and strontium is between 0.001 and 0.005%.
Claim 5
Dependent Claim
23 words
A steel according to claim 1, characterised in that it contains in additon one at least of the two elements selenium and tellurium.
Claim 6
Dependent Claim
23 words
A steel according to claim 2, characterised in that it contains in addition one at least of the two elements selenium and tellurium.
Claim 7
Dependent Claim
23 words
A steel according to claim 3, characterised in that it contains in addition one at least of the two elements selenium and tellurium.
Claim 8
Dependent Claim
30 words
A steel according to claim 4, characterised in that the selenium content is at least equal to two tenths of the sulfur content and at the most equal to 0.02%.
Claim 9
Dependent Claim
30 words
A steel according to claim 5, characterised in that the selenium content is at least equal to two tenths of the sulfur content and at the most equal to 0.2%.
Claim 10
Dependent Claim
30 words
A steel according to claim 6, characterised in that the selenium content is at least equal to two tenths of the sulfur content and at the most equal to 0.2%.
Claim 11
Dependent Claim
30 words
A steel according to claim 4, characterised in that the tellurium content is at least equal to five hundredths of the sulfur content and at the most equal to 0.04%.
Claim 12
Dependent Claim
30 words
A steel according to claim 4, characterised in that the tellurium content is at least equal to five hundredths of the sulfur content and at the most equal to 0.04%.
Claim 13
Dependent Claim
30 words
A steel according to claim 6, characterised in that the tellurium content is at least equal to five hundredths of the sulfur content and at the most equal to 0.04%.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-25 | 1980-07-26 | 1981-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-25 | 1984-07-26 | 1985-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-25 | 1988-07-26 | 1989-01-25 | $7700.00 | Window Closed / Lapsed |