Patent US2902357A successfully refreshed from Google Patents.
US2902357A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Increasing the density of iron powder by alternate rolling and grinding
Assignee: Republic Steel Corp
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Filing: 1954-06-11
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Granted: 1959-09-01
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Expires: 1974-06-11
Abstract
No abstract record available.
Inventors
- 👤 Sheridan R Crooks
- 👤 William A Reed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:31
CPC Classifications
B; B22; B22F; B22F9/00; B22F9/02; B22F9/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
185 words
THE METHOD OF TREATING IRON, WHICH WAS REDUCED TO THE METALLIC STATE FROM AN IRON COMPOUND UNDER CONDITIONS SUCH THAT THE METALLIC IRON PRODUCED WAS NOT MELTED OR FIRMLY SINTERED TOGETHER, WHILE PREVENTING WORKHARDENING AND INCREASING THE BULK DENSITY THEREOF, SO AS TO PROVIDE AND IRON POWDER HAVING A BULK DENSITY AND FLOW CHARACTERISTICS SUCH THAT IT IS USEFUL IN POWDER METALLURGY, SAID METHOD COMPRISING THE STEPS OF COMMINUTING THE REDUCED IRON SOLELY BY ATTRITION TO PRODUCE AN IRON POWDER HAVING A BULK DENSITY IN THE RANGE OF ABOUT 1.8 TO ABOUT 2.2 GRAMS PER CC., COMPACTING THE POWDER THUS PRODUCED SOLELY BY ROLLING IT BETWEEN SAMOOTH SURFACE ROLLS AND WITHOUT POSITIVELY HEATING IT TO PRODUCE A FRANGIBLE SHEET HAVING A BULK DENSITY OF ABOUT 3 TO ABOUT 4 GRAMS PER CC., AND THEREAFTER COMMINUTING SAID FRAGIBLE SHEET SOLEY BY ATTRITION TO PROVIDE AND IRON POWDER HAVING A BULK DENSITY IN THE RANGE OF ABOUT 2.3 TO ABOUT 2.5 GRAMS PER CC., AND WHICH IS NOT SUBSTANTIALLY WORKHARDENED AS COMPARED WITH THE IRON SUPPLIED TO OR THAT AT ANY EARLIER STAGE OF THE METHOD AFORESAID.
Claim 2
Independent Claim
185 words
THE METHOD OF TREATING IRON, WHICH WAS REDUCED TO THE METALLIC STATE FROM AN IRON COMPOUND UNDER CONDITIONS SUCH THAT THE METALLIC IRON PRODUCED WAS NOT MELTED OR FIRMLY SINTERED TOGETHER, WHILE PREVENTING WORKHARDENING AND INCREASING THE BULK DENSITY THEREOF, SO AS TO PROVIDE AND IRON POWDER HAVING A BULK DENSITY AND FLOW CHARACTERISTICS SUCH THAT IT IS USEFUL IN POWDER METALLURGY, SAID METHOD COMPRISING THE STEPS OF COMMINUTING THE REDUCED IRON SOLELY BY ATTRITION TO PRODUCE AN IRON POWDER HAVING A BULK DENSITY IN THE RANGE OF ABOUT 1.8 TO ABOUT 2.2 GRAMS PER CC., COMPACTING THE POWDER THUS PRODUCED SOLELY BY ROLLING IT BETWEEN SAMOOTH SURFACE ROLLS AND WITHOUT POSITIVELY HEATING IT TO PRODUCE A FRANGIBLE SHEET HAVING A BULK DENSITY OF ABOUT 3 TO ABOUT 4 GRAMS PER CC., AND THEREAFTER COMMINUTING SAID FRAGIBLE SHEET SOLEY BY ATTRITION TO PROVIDE AND IRON POWDER HAVING A BULK DENSITY IN THE RANGE OF ABOUT 2.3 TO ABOUT 2.5 GRAMS PER CC., AND WHICH IS NOT SUBSTANTIALLY WORKHARDENED AS COMPARED WITH THE IRON SUPPLIED TO OR THAT AT ANY EARLIER STAGE OF THE METHOD AFORESAID.
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) | 1962-08-31 | 1963-03-02 | 1963-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-31 | 1967-03-02 | 1967-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-31 | 1971-03-02 | 1971-09-01 | $7700.00 | Window Closed / Lapsed |