US4741786A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cold drawn free-machining steel bar including bismuth
Assignee: Republic Engineered Steels Inc
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Filing: 1986-06-10
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Granted: 1988-05-03
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Expires: 2006-06-10
Abstract
Abstract A cold drawn free-machining steel bar having a composition consisting essentially of, in weight percent, C up to 0.15; Mn 0.7 to 1.3; P 0.03 to 0.09; S 0.30 to 0.50; Bi 0.05 to 0.25; the sum of Ni, Cr, Mo and Cu up to 0.15 and the balance iron. The ratio % Mn / %S is from 1.7 to 3.0 and the %Mn-1.62×%S is from 0.05 to 0.40. The ratio %Bi /(%Ni+%Cu) is at least 2.0. The yield strength of the steel bar is further determined by the draft in cold drawing the bar from the hot rolled state and the cross section of the bar prior to draft.
Inventors
- 👤 Stephen P. Birman
- 👤 Richard B. Smith
- 👤 Richard L. Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:52
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/60; C21; C21D; C21D8/00; C21D8/06; C22C38/001; C22C38/002; C22C38/04; C22C38/14
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
80 words
A cold drawn free-machining steel bar having a composition consisting essentially of, in weight percent: C up to 0.15 Mn 0.7 to 1.3 P 0.03 to 0.09 S 0.30 to 0.50 Bi 0.05 to 0.25 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S is from 1.7 to 2.8 the %Mn - 1.62 X %S is from 0.05 to 0.40; and the ratio %Bi / (%Ni +%Cu) is at least 2.0.
Claim 2
Dependent Claim
80 words
A cold drawn free-machining steel bar having a composition consisting essentially of, in weight percent: C up to 0.15 Mn 0.7 to 1.3 P 0.03 to 0.09 S 0.30 to 0.50 Bi 0.05 to 0.25 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S is from 1.7 to 2.8 the %Mn - 1.62 X %S is from 0.05 to 0.40; and the ratio %Bi / (%Ni +%Cu) is at least 2.0.
Claim 3
Dependent Claim
18 words
The cold drawn steel bar of claim 1 further including, in weight percent, Pb from 0.05 to 0.15.
Claim 4
Dependent Claim
18 words
The cold drawn steel bar of claim 1 further including, in weight percent, Zr from 0.005 to 0.05.
Claim 5
Dependent Claim
18 words
The cold drawn steel bar of claim 1 further including, in weight percent, Te from 0.002 to 0.1.
Claim 6
Dependent Claim
18 words
The cold drawn steel bar of claim 1 further including, in weight percent, N from 0.006 to 0.012.
Claim 7
Dependent Claim
107 words
A cold drawn free-machining steel bar formed by cold drawing hot rolled coil, said bar having a composition consisting essentially of, in weight percent: C 0.07 to 0.09 Mn 0.7 to 0.9 S 0.30 to 0.40 P 0.03 to 0.07 Bi 0.05 to 0.15 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S is from 1.7 to 2.8; the %Mn - (1.62 X %S) is from 0.05 to 0.30; the ratio %Bi / (%Ni +%Cu) is at least 2.0; and the reduction in area in cold drawing the bar from hot rolled coil is from 10% to 30%.
Claim 8
Dependent Claim
107 words
A cold drawn free-machining steel bar formed by cold drawing hot rolled coil, said bar having a composition consisting essentially of, in weight percent: C 0.07 to 0.09 Mn 0.7 to 0.9 S 0.30 to 0.40 P 0.03 to 0.07 Bi 0.05 to 0.15 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S is from 1.7 to 2.8; the %Mn - (1.62 X %S) is from 0.05 to 0.30; the ratio %Bi / (%Ni +%Cu) is at least 2.0; and the reduction in area in cold drawing the bar from hot rolled coil is from 10% to 30%.
Claim 9
Dependent Claim
38 words
The cold drawn steel bar of claim 6 further characterized in that the reduction in area from cold drawing the bar is from 10% to 20%, providing a yield strength of on the order of about 60 ksi.
Claim 10
Dependent Claim
38 words
The cold drawn steel bar of claim 6 further characterized in that the reduction in area from cold drawing the bar is from 20% to 30%, providing a yield strength of on the order of about 70 ksi.
Claim 11
Dependent Claim
42 words
The cold drawn steel bar of claim 6 further characterized in that the hot rolled coil has a hexagonal shape, the cold drawn bar having a hexagonal shape and the reduction in area from cold drawing the bar is from 10% to
Claim 12
Dependent Claim
108 words
A cold drawn free-machining steel bar formed by cold drawing a hot rolled bar up to two inches in diameter, said bar having a composition consisting essentially of, in weight percent: C 0.09 to 0.11 Mn 0.9 to 1.1 S 0.36 to 0.46 P 0.04 to 0.08 Bi 0.05 to 0.15 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S being 1.9 to 2.8; the %Mn - (1.62 X %S) being 0.15 to 0.40; the ratio %Bi / (%Ni +%Cu) is at least 2.0; and the reduction of area in cold drawing the bar is from 6% to 10%.
Claim 13
Dependent Claim
108 words
A cold drawn free-machining steel bar formed by cold drawing a hot rolled bar up to two inches in diameter, said bar having a composition consisting essentially of, in weight percent: C 0.09 to 0.11 Mn 0.9 to 1.1 S 0.36 to 0.46 P 0.04 to 0.08 Bi 0.05 to 0.15 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S being 1.9 to 2.8; the %Mn - (1.62 X %S) being 0.15 to 0.40; the ratio %Bi / (%Ni +%Cu) is at least 2.0; and the reduction of area in cold drawing the bar is from 6% to 10%.
Claim 14
Dependent Claim
38 words
The cold drawn steel bar of claim 10 further characterized in that the reduction in area from cold drawing the bar is from 6% to 8%, providing a yield strength of on the order of about 60 ksi.
Claim 15
Dependent Claim
38 words
The cold drawn steel bar of claim 10 further characterized in that the reduction in area from cold drawing the bar is from 8% to 10%, providing a yield strength of on the order of about 70 ksi.
Claim 16
Dependent Claim
110 words
A cold drawn free-machining steel bar formed by cold drawing a hot rolled bar having a diameter at least two inches, the bar having a composition consisting essentially of, in weight percent: C b 0.06 to 0.13 Mn 0.8 to 1.3 P 0.06 to 0.09 S 0.32 to 0.50 Bi 0.15 to 0.25 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S being 2.0 to 2.8 the %Mn -.1 62 X %S being 0.2 to 0.4; the ratio %Bi / (%Ni +%Cu) is at least 2.0; and the reduction of area in cold drawing the bar is from 3% to 6%.
Claim 17
Dependent Claim
110 words
A cold drawn free-machining steel bar formed by cold drawing a hot rolled bar having a diameter at least two inches, the bar having a composition consisting essentially of, in weight percent: C b 0.06 to 0.13 Mn 0.8 to 1.3 P 0.06 to 0.09 S 0.32 to 0.50 Bi 0.15 to 0.25 The sum of Ni, Cr, Mo and Cu up to 0.15; balance iron; the ratio %Mn / %S being 2.0 to 2.8 the %Mn -.1 62 X %S being 0.2 to 0.4; the ratio %Bi / (%Ni +%Cu) is at least 2.0; and the reduction of area in cold drawing the bar is from 3% to 6%.
Claim 18
Dependent Claim
49 words
The cold drawn steel bar of claim 13 further characterized in that the bar has a round or square cross section and has a composition essentially of, in weight C 0.10 to 0.13 Mn 1.0 to 1.3 P 0.06 to 0.09 S 0.40 to 0.50 Bi 0.15 to 0.25.
Claim 19
Dependent Claim
63 words
The cold drawn steel bar of claim 13 further characterized in that the bar has a hexagon shape and has a composition consisting essentially of, in weight percent: C 0.06 to 0.08 Mn 0.8 to 1.0 P 0.06 to 0.09 S 0.32 to 0.40 Bi 0.15 to 0.25; and the reduction of area in cold drawing the bar is from 3% to 5%.
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) | 1991-05-03 | 1991-11-02 | 1992-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-03 | 1995-11-02 | 1996-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-03 | 1999-11-02 | 2000-05-03 | $7700.00 | Window Closed / Lapsed |