US3769008A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for sintering workpieces of pressed powdered refractory metal or alloy and vacuum furnace for performing the same
Assignee: Individual
•
Filing: 1971-05-19
•
Granted: 1973-10-30
•
Expires: 1991-05-19
Abstract
Abstract A method for sintering workpieces of a pressed powdered refractory metal in vacuum. The method envisages simultaneous heating of the workpiece by electron bombardment over its entire surface. The workpiece to be treated is heated to a temperature which makes from 10 to 15 per cent of its material melting temperature and is at such temperature till gases cease to evolve therefrom. A vacuum furnace for performing the method has a heater made as a cathode surrounding the entire surface of the workpiece to be treated and placed at a uniform distance from the workpiece.
Inventors
- 👤 B Borok
- 👤 Z Dzneladze
- 👤 L Petrov
- 👤 B Lobashov
- 👤 E Zaikin
- 👤 I Kiyansky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:05
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/10; B22F3/105
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
73 words
A vacuum furnace for sintering workpieces, comprising a table for supporting the workpiece to be treated; means movably supporting the table inside said furnace; a heater constituted as a cathode surrounding the entire surface of said workpiece, said heater comprising a plurality of parallel elements encircling the workpiece in facing relation at a substantially uniform spacing therefrom; and an electrical lead-in connected with said heater and with sources of high and heating voltages.
Claim 2
Dependent Claim
29 words
A vacuum furnace as claimed in claim 2 wherein said parallel heater elements extend substantially beyond the ends of the workpiece for heating the end faces of the workpiece.
References Cited (Backward Citations)
US2227177A
Cited
US2809905A
Cited
US2942098A
Cited
US2994801A
Cited
US3183086A
Cited
US3381157A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |