US3792997A - Aluminum-copper-magnesium powder metallurgy - Google Patents

Aluminum-copper-magnesium powder metallurgy Download PDF

Info

Publication number
US3792997A
US3792997A US00254013A US3792997DA US3792997A US 3792997 A US3792997 A US 3792997A US 00254013 A US00254013 A US 00254013A US 3792997D A US3792997D A US 3792997DA US 3792997 A US3792997 A US 3792997A
Authority
US
United States
Prior art keywords
copper
powder
aluminum
percent
magnesium
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00254013A
Other languages
English (en)
Inventor
S Storchheim
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US3792997A publication Critical patent/US3792997A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/0408—Light metal alloys
    • C22C1/0416—Aluminium-based alloys

Definitions

  • This invention relates to aluminum powder metallurgy and, more particularly, to aluminum-coppermagnesium powder mixtures which yield sintered compacts of improved mechanical properties.
  • the copper powder for producing high strength products has been in the form of both massive and flake-like particles.
  • the flake-shaped particles when used, have been of the leafing type which, when suspended in a liquid vehicle and applied as a lacquer or paint, arrange themselves in planes parallel to the surface to which they are applied.
  • the advantage of using leafing-type copper flake is that the surface of the flake contains a sufficient quantity of stearic acid, which produces the leafing" property, to promote mixing of the copper with the aluminum powder and to act as a lubricant facilitating compaction of the resulting aluminum-copper powder mixture.
  • the leafing type copper flake powders contain about 0.5 to 2 percent by weight of stearic acid or oleic acid on their surfaces, as described in U. 5. Pat. No. 3,333,950, although commercially available leafing copper powders generally contain about I to-2 percent by weight of stearic or oleic acid.
  • Commercially available non-leafing copper flake powders usually contain from about 0.13 to 0.25 percent by weight of stearic acid added as a lubricant in the milling process required to convert massive copper particles into flakes, and when these nonleafing copper flake powders are added to aluminum powder they totally resist distribution through the aluminum powder even after 24 hours of continuous mixmg.
  • the novel powder mixture of the invention can use virtuallyall grades of aluminum powder, the only limitation being that the finer the powder the poorer its flow rate for discharge into a die under commercial operating conditions.
  • Alcoas aluminum powder No. 1220 (9.7 percent minus 325 mesh Tyler), No. 120 (35.6 percent minus 325 mesh) and No. 123
  • a small amount of magnesium in the powder mixture of the invention accelerates or activates sintering of the mixture by forming a relatively lower melting point eutectic with the aluminum.
  • the amount of magnesium useful for this purpose ranges between about 0.2 to 2 weight percent of the aluminum powder. Within this range, amounts of magnesium from 0.3 to 0.6 weight percent of the aluminum are presently preferred.
  • the magnesium can be added as magnesium metal powder or in the form of a magnesium alloy powder.
  • the alloying constituent one of the other components of the powder mixture, such as aluminum or copper (i.e., aluminum-magnesium and copper-magnesium alloy powders) but other alloying constituents which are advantageous for, or at least not inimicable to, the desired properties of the sintered compact can be used in conjunction with the magnesium component of the mixture.
  • the copper flake powder is used in the powder mixtures of the invention in amounts ranging from 2 to 6 weight percent of the aluminum component. Amounts of copper of at least about 2 percent are required to impart age-hardening characteristics to sintered compacts made from the mixture, and amounts of copper in excess of about 6 percent increase the strength and hardness of the sintered compacts at too much expense in loss of ductility.- An amount of copper powder about 4 percent by weight of the aluminum powder presently appears to give a generally optimum combination of physical and mechanical properties.
  • the copper flake powder used in the metal powder mixtures of the invention must be of the non-leafing type but must contain the so-called leafing organic coating in amount limited to between about 0.03 and 0.05 weight percent of the copper flake.
  • Copper flake powders are produced by flattening conventional copper particles of massive shape in the presence of a lubricating or polishing organic compound such as stearic acid, oleic acid, zinc stearate, lithium stearate, and the like.
  • a lubricating or polishing organic compound such as stearic acid, oleic acid, zinc stearate, lithium stearate, and the like.
  • Aluminum-copper-magnesium powder mixtures of the invention characterized by the presence of the copper in non-leafing" flake form containing from about 0.03 to 0.05 percent by weight of organic flaking lubricant, are further characterized by the absence of any additional quantity of the same or similar conventional powder-metallurgy internal lubricants.
  • the compacted powder mixtures of the invention can be sintered in any furnace atmosphere ranging from oxidizing to neutral to reducing in nature.
  • the compacted powder mixtures of the invention can be sintered in air, steam, smelting furnace gases containing a variety of proportions of carbon monoxide and carbon dioxide, hydrogen, nitrogen, cracked ammonia, etc.
  • FIG. 1 is a plot of mechanical properties versus mixing time for 4 inches X /2 inch X /8 inch bars that were green pressed to 95 percent theoretical density and then air sintered at l,l F. in a furnace through which they pass at a 2 /2 inches per minute belt speed (four minutes at temperature) with the furnace atmosphere consisting of ambient air.
  • FIG. 2 shows that the number of bend-to-fracture peaks to a maximum value at six hours mixing time while the difference in sintered lengths among the 4 inch long bars were at a minimum at the six hours mixing time.
  • FIG. 3 shows an approximately 20 percent drop in growth (which occurs in air sintering) over the 4 inch lengths following sintering using the six hour mixing time blend.
  • Bar samples of both the aforementioned copper flake mixture of the invention (six hours mixing time), and bar samples of the same mixture except for the use of conventional copper powder, were sintered and were then immediately quenched in room-temperature water upon emerging from a continuous belt sintering furnace. Bars containing the copper flake, when quenched from 550C. and after five days of ageing, developed an U.T.S. of 34,370 psi and an elongation of 4.0 percent. Bars made with the conventional copper powder reached a maximum U.T.S. of 32,000 psi with a 1.8 percent elongation.
  • An aluminum-copper-magnesium powder mixture adapted to be compacted and sintered to an agehardenable product which comprises an intimate mixture of metal powders free from internally lubricating amount of any organic material and consisting essentially of aluminum powder, about 2 to 6 weight percent of non-leafing copper flake powder containing on its surface between about 0.03 to 0.05 weight percent of a leafing-type lubricant, and about 0.2 to 2 weight percent of magnesium in powder form.
  • a powder mixture according to claim 1 which has been physically mixed for a continuous period of at least /2 hour.
  • a powder mixture according to claim 1 which has been physically mixed for a continuous period of at least 1% hours.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)
US00254013A 1972-05-17 1972-05-17 Aluminum-copper-magnesium powder metallurgy Expired - Lifetime US3792997A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US25401372A 1972-05-17 1972-05-17

Publications (1)

Publication Number Publication Date
US3792997A true US3792997A (en) 1974-02-19

Family

ID=22962590

Family Applications (1)

Application Number Title Priority Date Filing Date
US00254013A Expired - Lifetime US3792997A (en) 1972-05-17 1972-05-17 Aluminum-copper-magnesium powder metallurgy

Country Status (2)

Country Link
US (1) US3792997A (US20110158925A1-20110630-C00042.png)
IN (1) IN139648B (US20110158925A1-20110630-C00042.png)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4600556A (en) * 1983-08-08 1986-07-15 Inco Alloys International, Inc. Dispersion strengthened mechanically alloyed Al-Mg-Li
US20110265757A1 (en) * 2008-10-10 2011-11-03 Donald Paul Bishop Aluminum alloy powder metal bulk chemistry formulation

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3250838A (en) * 1964-08-04 1966-05-10 Alloys Res & Mfg Corp Techniques for compacting aluminum powder mixtures
US3333950A (en) * 1964-10-06 1967-08-01 Engelhard Ind Inc Metal composition for powder metallurgy moldings and method for production
US3357818A (en) * 1964-09-02 1967-12-12 Mannesmann Ag Metallurgical powder mixtures and mixing methods therefor
US3401033A (en) * 1961-03-09 1968-09-10 Bliss E W Co Method of blending powdered metal and lubricant prior to sintering

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3401033A (en) * 1961-03-09 1968-09-10 Bliss E W Co Method of blending powdered metal and lubricant prior to sintering
US3250838A (en) * 1964-08-04 1966-05-10 Alloys Res & Mfg Corp Techniques for compacting aluminum powder mixtures
US3357818A (en) * 1964-09-02 1967-12-12 Mannesmann Ag Metallurgical powder mixtures and mixing methods therefor
US3333950A (en) * 1964-10-06 1967-08-01 Engelhard Ind Inc Metal composition for powder metallurgy moldings and method for production

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4600556A (en) * 1983-08-08 1986-07-15 Inco Alloys International, Inc. Dispersion strengthened mechanically alloyed Al-Mg-Li
US20110265757A1 (en) * 2008-10-10 2011-11-03 Donald Paul Bishop Aluminum alloy powder metal bulk chemistry formulation
US8920533B2 (en) * 2008-10-10 2014-12-30 Gkn Sinter Metals, Llc Aluminum alloy powder metal bulk chemistry formulation

Also Published As

Publication number Publication date
IN139648B (US20110158925A1-20110630-C00042.png) 1976-07-10

Similar Documents

Publication Publication Date Title
DE2437522C3 (de) Verfahren zum Herstellen eines Schleifkörpers
US3740210A (en) Mechanically alloyed aluminum aluminum oxide
US4799955A (en) Soft composite metal powder and method to produce same
US3836355A (en) Steel powder containing phosphorus
DE1125459C2 (de) Verfahren zum Erzeugen von legiertem Pulver auf Eisenbasis fuer pulvermetallurgische Zwecke
US3953202A (en) Phosphorus-bearing master composition for addition to hyper-eutectic silicon-aluminum casting alloys and process therefor
DE69430904T2 (de) Pulver aus Eisenschwamm
US3792997A (en) Aluminum-copper-magnesium powder metallurgy
US3583864A (en) Chemical process of producing an iron-copper alloy powder
US3708282A (en) Production of sintered metal products
US3196007A (en) Beryllium copper composition and method of producing green compacts and sintered articles therefrom
EP0099219B1 (en) Method of producing an agglomerated metallurgical composition
US4702772A (en) Sintered alloy
DE1170651B (de) Verfahren zum Herstellen von dispersionsgehaerteten Metallkoerpern
US4404023A (en) Process for the production of a metal or metal alloy powder
US3627862A (en) Treatment of metal powder
US4518427A (en) Iron or steel powder, a process for its manufacture and press-sintered products made therefrom
DE2013038A1 (de) Verfahren zur Herstellung von Kupfer oder Silber enthaltenden Wolfram- und/oder Molybdän-Pulverzusammensetzungen
US3895942A (en) Strong, high purity nickel
US2657128A (en) Silicon-alloyed corrosion-resistant metal powders and related products and processes
US3333950A (en) Metal composition for powder metallurgy moldings and method for production
US3383198A (en) High green strength-low density copper powder and method for preparing same
DE2436588A1 (de) Dispersionsgehaertete werkstoffe und verfahren zu ihrer herstellung
DE3011962A1 (de) Metallkomposition und verfahren zu deren herstellung
WO1993018195A1 (de) Verfahren zur herstellung eines sinterkörpers aus hochlegiertem stahlpulver