Patent US4002474A successfully refreshed from Google Patents.
US4002474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lubricants for powdered metals
Assignee: HL Blachford Ltd
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Filing: 1975-07-31
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Granted: 1977-01-11
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Expires: 1995-07-31
Abstract
Abstract Discrete pressure-rupturable microcapsules for lubrication in powder metallurgy are disclosed comprising a core and a solid shell surrounding said core; the core comprises an organic liquid lubricant able to wet powdered metals, the shell comprises a thin non-atmospherically degradable polymeric material; the microcapsules may be used as the sole lubricant in the manufacture of sintered metal parts or may be used in admixture with other solid lubricants to produce beneficial synergistic effects.
Inventors
- 👤 John Blachford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:59
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/14; B01J13/16; B22; B22F; B22F1/00; B22F1/10; B22F3/00; B22F3/02; C; C10; C10M; C10M177/00; B22F2003/023; C10M2201/00; C10M2201/04; C10M2201/041; C10M2201/042; C10M2201/06; C10M2201/065; C10M2201/066; C10M2201/08; C10M2201/082; C10M2201/083; C10M2205/00; C10M2205/02; C10M2205/022; C10M2205/04; C10M2205/14; C10M2205/16; C10M2205/17; C10M2205/18; C10M2207/00; C10M2207/10; C10M2207/12; C10M2207/125; C10M2207/129; C10M2207/28; C10M2207/281; C10M2207/282; C10M2207/283; C10M2207/286; C10M2207/40; C10M2207/404; C10M2209/00; C10M2209/10; C10M2209/103; C10M2209/105; C10M2215/00; C10M2215/08; C10M2215/082; C10M2215/24; C10M2215/28; C10M2217/00; C10M2217/04; C10M2217/044; C10M2217/045; C10M2219/00; C10M2219/04; C10M2219/044; C10M2223/00; C10M2223/02; C10M2223/04; C10M2223/041; C10M2223/045; C10N; C10N2010/00; C10N2010/02; C10N2010/04; C10N2040/00; C10N2040/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
101 words
A method of producing a sintered metal part from powdered metal comprising blending said powdered metal with a lubricant comprising discrete pressure-rupturable microcapsules comprising a core of a non-corrosive liquid organic lubricant able to wet said powdered metal, and surrounding said core a thin polymeric solid shell, to form an intimate mixture, compacting said mixture in a mould at a pressure effective to rupture said shell and release said liquid lubricant and to form said mixture into a self-supporting shaped body, removing said body from said mould, heating said body to decompose and remove organic material, and sintering said metal particles.
Claim 2
Independent Claim
101 words
A method of producing a sintered metal part from powdered metal comprising blending said powdered metal with a lubricant comprising discrete pressure-rupturable microcapsules comprising a core of a non-corrosive liquid organic lubricant able to wet said powdered metal, and surrounding said core a thin polymeric solid shell, to form an intimate mixture, compacting said mixture in a mould at a pressure effective to rupture said shell and release said liquid lubricant and to form said mixture into a self-supporting shaped body, removing said body from said mould, heating said body to decompose and remove organic material, and sintering said metal particles.
Claim 3
Dependent Claim
24 words
A method according to claim 1 wherein said lubricant is a synergistic mixture of said microcapsules and a solid unencapsulated particulate powder metallurgy lubricant.
Claim 4
Dependent Claim
24 words
A method according to claim 1 wherein said shell has at its outer surface a thin coating of a solid lubricant for metal powders.
Claim 5
Dependent Claim
15 words
A method according to claim 1 wherein said powdered metal is a powdered metal alloy.
Claim 6
Dependent Claim
16 words
A method according to claim 1 wherein said powdered metal is a mixture of metal powders.
Claim 7
Dependent Claim
13 words
A method according to claim 1 wherein said powdered metal comprises iron powder.
Claim 8
Dependent Claim
15 words
A method according to claim 6 wherein said iron powder contains graphite as an additive.
Claim 9
Dependent Claim
16 words
A method according to claim 1 wherein said liquid organic lubricant comprises a fatty acid ester.
Claim 10
Dependent Claim
14 words
A method according to claim 2 wherein said unencapsulated lubricant is an amide wax.
Claim 11
Dependent Claim
12 words
A method according to claim 9 wherein said amide wax is ethylenebisstearamide.
Claim 12
Dependent Claim
14 words
A method according to claim 2 wherein said unencapsulated lubricant is a metal stearate.
Claim 13
Dependent Claim
13 words
A method according to claim 11 wherein said metal stearate is zinc stearate.
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) | 1980-01-11 | 1980-07-12 | 1981-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-11 | 1984-07-12 | 1985-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-11 | 1988-07-12 | 1989-01-11 | $7700.00 | Window Closed / Lapsed |