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US3987730A Expired / Lapsed US ⏱️ 0.0 years remaining

Iron and lead-containing composite metal shot

Assignee: National Research Council Canada
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Filing: 1975-02-03
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Granted: 1976-10-26
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Expires: 1995-02-03
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Abstract

Abstract Composite metal articles of high density are made from iron and lead or a lead-rich alloy in proportions suitably of about 25 to about 90 wt. % iron, when present up to about 5 wt. % of a lead alloy-forming element aiding wetting of the iron, and the balance substantially all lead. Preferably copper, zinc, tin, indium or mixtures thereof are present to aid wetting the iron phase. Composite bird shot, for instance, is prepared e.g. by matrix formation and infiltration, or by agglomeration techniques, or by other techniques, with, if desired, a final mechanical shaping or compaction. The presence of iron has been found to cause a significant reduction in toxicity to birds on ingestion.

Inventors

  • 👤 Frederick Weldon Meadus
  • 👤 Bryan D. Sparks
  • 👤 Ira E. Puddington

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 23:14
CPC Classifications
B; B22; B22F; B22F9/00; B22F9/02; B22F9/04; F; F42; F42B; F42B7/00; F42B7/02; F42B7/04; F42B7/046; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12042; Y10T428/1216; Y10T428/12181; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12951; Y10T428/12958

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 84 words
Composite metal bird shot of substantially theoretical density and reduced toxicity comprising iron and lead wherein the iron is a separate phase in discrete or porous matrix form, surrounded and interpenetrated by the lead phase, the lead phase being selected from lead and lead alloyed with up to about 5% weight based on the composite of an alloying element aiding wetting of the iron surfaces, and wherein the separate iron phase is present in from about 25 to about 90% weight of the composite.
Claim 2
Dependent Claim 84 words
Composite metal bird shot of substantially theoretical density and reduced toxicity comprising iron and lead wherein the iron is a separate phase in discrete or porous matrix form, surrounded and interpenetrated by the lead phase, the lead phase being selected from lead and lead alloyed with up to about 5% weight based on the composite of an alloying element aiding wetting of the iron surfaces, and wherein the separate iron phase is present in from about 25 to about 90% weight of the composite.
Claim 3
Dependent Claim 26 words
The composite metal bird shot of claim 1 wherein the separate iron phase is present in from about 40 to about 70% wt. of the composite.
Claim 4
Dependent Claim 37 words
The composite metal bird shot of claim 2 wherein an alloying element is present and selected from the group consisting of copper, zinc, tin, indium and mixtures thereof, and the lead phase intimately wets the iron surfaces.
Claim 5
Dependent Claim 24 words
The composite metal bird shot of claim 3 wherein the alloying element is present in about 0.5 to about 1.5% wt. of the composite.
Claim 6
Dependent Claim 24 words
The composite metal bird shot of claim 2 wherein the iron phase consists of iron particles which are in substantial contact with each other.
Claim 7
Dependent Claim 17 words
The composite metal bird shot of claim 2 wherein the iron phase is a porous matrix structure.
Claim 8
Dependent Claim 18 words
The composite metal bird shot of claim 3 wherein zinc is present together with either copper or tin.
Claim 9
Dependent Claim 45 words
The composite metal bird shot of claim 3 having the following composition: iron phase in about 40 to about 70% wt. copper or tin in about 0.05 to about 1.5% wt., zinc in about 0.05 to about 1.5% wt., and the balance substantially all lead.
Claim 10
Dependent Claim 41 words
The composite metal bird shot of claim 3 comprising a sintered composite mixture of iron powder and lead alloyed powder, the iron being substantially un-alloyed except at the surfaces thereof but wetted and bonded by an alloy of the other metals.
Claim 11
Dependent Claim 22 words
The bird shot of claim 9 containing a preformed nucleus surrounded by said iron phase surrounded and interpenetrated by said lead phase.
Claim 12
Dependent Claim 14 words
The composite metal bird shot of claim 1 compacted and shaped by mechanical means.
Claim 13
Dependent Claim 17 words
The bird shot of claim 9 wherein the lead phase is more concentrated toward the pellet surface.
Claim 14
Dependent Claim 14 words
The bird shot of claim 10 wherein the performed necleus is an iron core.

References Cited (Backward Citations)

US2033240A Cited
DE1094780B Cited
US3301642A Cited
US3363561A Cited
US3463637A Cited
US3664824A Cited
US3900317A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-10-26 1980-04-26 1980-10-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-10-26 1984-04-26 1984-10-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-10-26 1988-04-26 1988-10-26 $7700.00 Window Closed / Lapsed

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