Patent US4574174A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3729293A Expired / Lapsed US ⏱️ 0.0 years remaining

Lead-bearing steel and method of manufacture

Assignee: Crucible Materials Corp
•
Filing: 1971-04-30
•
Granted: 1973-04-24
•
Expires: 1991-04-30
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract THIS INVENTION RELATES TO A TOOL-STEEL COMPOSITION CHARACTERIZED BY IMPROVED MACHINABILITY BY THE ADDITION OF .5 TO 2% LEAD IN COMBINATION WITH SULFUR IN AN AMOUNT UP TO ABOUT .3%. ARTICLES CHARACTERIZED BY IMPROVED MACHINABILITY ARE PRODUCED IN ACCORDANCE WITH THE PRESENT INVENTION BY PROVIDING A CHARGE OF POWDERED METAL OF A DESIRED TOOL-STEEL COMPOSITION, COATING THE PARTICLES WITH LEAD OXIDE, THEREAFTER HEATING SAID CHARGE UNDER CONDITIONS OF TEMPERATURE AND PRESSURE TO DECOMPOSE SAID LEAD OXIDE BY GASSIFICATION AND THEN REMOVING THE PRODUCTS OF GASSIFICATION FROM THE POWDERED METAL CHARGE TO LEAVE THE PARTICLES COATED WITH LEAD. THE LEAD-CONTAINING CHARGE OF PARTICLES IS THEN COMPACTED TO FORM A DENSE COMPACT.

Inventors

  • 👤 G Steven

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:10
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; C22C38/00; C22C38/60; Y; Y10; Y10S; Y10S75/00; Y10S75/95

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

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) 1976-04-23 1976-10-23 1977-04-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-04-23 1980-10-23 1981-04-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-04-23 1984-10-23 1985-04-24 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag