US3489548A - Particulate powder of iron with copper contained therein - Google Patents

Particulate powder of iron with copper contained therein Download PDF

Info

Publication number
US3489548A
US3489548A US471767A US3489548DA US3489548A US 3489548 A US3489548 A US 3489548A US 471767 A US471767 A US 471767A US 3489548D A US3489548D A US 3489548DA US 3489548 A US3489548 A US 3489548A
Authority
US
United States
Prior art keywords
copper
iron
sintered
reduction
powder
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
US471767A
Other languages
English (en)
Inventor
Arthur Adler
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.)
Pfizer Inc
Original Assignee
Pfizer Inc
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 Pfizer Inc filed Critical Pfizer Inc
Application granted granted Critical
Publication of US3489548A publication Critical patent/US3489548A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/30—Making metallic powder or suspensions thereof using chemical processes with decomposition of metal compounds, e.g. by pyrolysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/17—Metallic particles coated with metal
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/02—Making ferrous alloys by powder metallurgy
    • C22C33/0235—Starting from compounds, e.g. oxides
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S75/00—Specialized metallurgical processes, compositions for use therein, consolidated metal powder compositions, and loose metal particulate mixtures
    • Y10S75/956—Producing particles containing a dispersed phase
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S75/00—Specialized metallurgical processes, compositions for use therein, consolidated metal powder compositions, and loose metal particulate mixtures
    • Y10S75/962—Treating or using mill scale

Definitions

  • An alloy in powder form comprising iron intimately infiltrated with from about 1 to 50% by weight of copper.
  • the particulate alloy is produced by mixing a reducible compound of iron with an appropriate proportion-of a copper compound selected from the group consisting of elemental copper and reducible compounds of copper, the mixture being heated under reducing conditions at a temperature of up to about 1150 C. and at least about 100 C. above the sintering temperature for copper for a time until the reducible compounds are substantially completely reduced to the metal state.
  • This invention is concerned with alloys of copper and iron, and more particularly with novel iron powders preinfiltrated with copper, and with processes for their preparation.
  • an alloy is defined to be a substance having metallic properties and composed of two or more chemical elements of which at least one is elemental metal. It has in the past been recognized that the physical properties of iron are improved by alloying with copper. Since these metals are virtually insoluble in each other at room temperature, and sincetheir mutual solubility is quite limited even at elevated temperatures, various expedients have been employed in an attempt to bring them into intimate association. Thus, copper and iron powders have been blended and molded into finished objects by the techniques of powder metallurgy. In-addition, the infiltration process has been employed, i.e. filling the pores of a sintered powder metallurgy part, of iron or steel in this case, with a metal or alloy of lower melting point, e.g. copper.
  • Blended copper and iron powders are subject to segregation in storage and shipment. More important, even' very finely divided, blended powders do not provide the degree of homogeneity which affords optimum properties.
  • sintering of compacted copper-iron powder blends results in expansion of the compact, representing a porosity increase which is a major factor in interior strength, molding flaws and high rejection rate.
  • a relatively simple procedure has now been discovered for the preparation of novel copper-iron alloys in powder form, offering substantial cost advantages over conventional infiltration techniques. This procedure.
  • FIG. 1 illustrates an alloy of iron with 7% by weight of copper, prepared by the process of the present invention and enlarged approximately 100,000 diameters.
  • FIG. 2 shows the alloy of FIG. 1 after heat treatment as detailed hereinafter, also enlarged approximately 100,- 000 diameters.
  • FIG. 3 depicts an alloy of iron with 20% by weight of copper, prepared in accordance with the present invention and enlarged approximately 3600 diameters.
  • FIG. 4 shows the alloy of FIG. 3 after heat treatment, also enlarged approximately 3600 diameters.
  • FIG. 5 shows a portion of the particle depicted in FIG. 4, this time enlarged approximately 17,700 diameters.
  • the process of the present invention entails blending a reducible iron compound with copper or with a reducible copper compound, and reducing these reactants to the metallic state at elevated temperature.
  • the relative proportions are selected to yield a product containing from about 1 to about 50% by weight of copper.
  • reduction temperatures at or above the copper melting temperature tend to cause agglomeration of the reduced product to a mass which can be broken down into smaller particles only with great difficulty.
  • the reduction temperature below the melting point of copper, but still at least 100 C. above the copper sintering temperature, preferably at about 950- 1050 C.
  • the fullest advantage is obtained by conducting the reduction at or above the copper melting temperature, preferably at about 11201135 C.
  • reduction temperatures above about 1150 C. are undesirable, since they favor extensive product agglomeration, producing a tough, hard mass which is impossible to grind to metal powder by any economic means.
  • the reactant mixture is reduced to a particulate alloy of iron intimately infiltra ed with copper, without the need for the copper to flow through the mass of iron to saturate the pores as 3 is the case in conventional infiltration of molded iron compacts.
  • the oxide or other reducible iron compound undergoes a solid state reduction. Where the reduction is conducted below 1094 C., but at least 100 above the copper sintering temperature, the copper does not liquify, but the reduced solids undergo grain boundary diffusion, with comparable results.
  • These lower reduction temperatures are preferred in the production of alloys of high copper content, as previously discussed, and the high copper volume fractions are believed to favor products of infiltrated nature.
  • the new particulate alloys of the present invention are not subject to segregation into the individual elements in storage or shipment. They may be truly termed pre-infiltrated alloys, since they are directly moldable by conventional powder metallurgy techniques to useful parts, without the need for a separate penetration of liquid copper into a molded iron part as practiced in conventional infiltration.
  • reducible iron compound may be employed in the new process, including iron salts or any oxide of iron such as hematite, magnetite, beneficiated magnetite ores, fiue dusts, synthetic oxides or reducible mill scales, e.g. from rolling mill operations.
  • reducible mill scales is meant those which are reducible to the extent of about 99% or better, such as carbon steel mill scale and low alloy steel mill scales.
  • the source of copper may be elemental copper, such as reduced copper powder, atomized copper, electrolytic copper powder or hydrometallurgical copper powder.
  • elemental copper such as reduced copper powder, atomized copper, electrolytic copper powder or hydrometallurgical copper powder.
  • an oxide of copper either precipitated or mechanically produced, such as cuprous oxide, cupric oxide, copper mill scale, or cement copper, a byproduct of mine waste water which typically contains about 50-98% cuprous oxide.
  • copper oxides it is sometimes beneficial to incorporate nitric acid in the reaction charge, to promote a more intimate dispersion.
  • cupric nitrate or other water-soluble copper salt may be employed in water solution as the copper source.
  • nickel, cobalt, molybdenum or tungsten may be included, or reducible compounds of these elements, such as nickelous acetate, cobaltic oxide, molybdic oxide, or tungstic anhydride.
  • Such elements will generally be employed in minor proportion, i.e. up to about 6% by weight of any one element or a total of up to about 12% by weight in the case of several in combination, in order to improve strength.
  • Such elements may be added in the form of soluble salts such as nitrates or acetates, for optimum dispersion, or as compounds in combination with an acid or base solvent, such as ammonia water or nitric acid.
  • reactants which have particle sizes finer than 250 microns, and especially preferred are iron compounds finer than about 50 microns and copper compounds finer than about microns, since these favor the most intimate interdispersion of the elements.
  • Suitable binders include animal protein glue, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, and the like. Such compounds are readily decomposed at the reduction temperature and should preferably be low in ash content. Adhesive levels of about 0.5% of the total batch weight are usually entirely adequate, the proportion of water usually being up to about 18% of the total batch.
  • the blending of reactants may be advantageously conducted in a mix muller or chaser, which will form the ingredients into hard pellets up to about an inch in diameter with little or no secondary grinding. These pellets may be charged to the reduction furnace without drying. If no adhesive is employed, the reactants are thoroughly blended before charging to the furnace.
  • Reducing conditions may be provided within the furnace in the form of a gaseous reducing atmosphere, e.g. hydrogen or carbon monoxide, or sources of such agents including dissociated ammonia, water gas, producer gas and the like.
  • the reducing conditions may be provided by incorporating finely divided carbon within the reactant mixture.
  • Suitable forms of carbon include lamp black, petroleum coke, anthracite fines, carbon black, bone black or graphite.
  • the minimum-carbon levels being dependent on the particular reactants and reactant proportions, may be estimated from the stoichiometry of the reaction, but optimum levels are best determined by experiment. Carbon levels of about 812% are typical.
  • the reduction is continued until the reducible compounds are substantially completely reduced, i.e. about 93-98% reduced.
  • the product particles usually form a lightly sintered sponge, which may readily be subdivided to final particle size specifications by milling. It has been found that a residual oxygen content of 2% or more yields a particularly friable sponge which is broken up more easily than sponges of lower oxygen content.
  • the time required to carry the reduction to this level will vary with the reducing conditions and the particular reactants selected. Ordinarily, reduction is usually substantially complete in from about 30 minutes to two hours. It is undesirable to prolong the reduction unnecessarily, since reduction times longer than about two hours may lead to difiiculty in breaking up the sponge.
  • the product may be g ound in a hammer mill or pulverizer to final particle size specifications, generally to pass 60 or mesh.
  • the resulting powders may be molded into useful shapes by conventional powder metallurgy techniques, i.e. by compacting at about 1060 tons per square inch and then sintering under non-oxidizing conditions at elevated temperature, preferably at or above the melting point of copper for optimum properties.
  • powder metallurgy techniques i.e. by compacting at about 1060 tons per square inch and then sintering under non-oxidizing conditions at elevated temperature, preferably at or above the melting point of copper for optimum properties.
  • elevated temperature preferably at or above the melting point of copper for optimum properties.
  • any'expansion as a result of alloying occurs during the reduction step and not during the sintering of the compacted particles.
  • the sinterin got these new alloys represents a consolidation of the pre-infiltrated or alloyed particles, with further alloying" occurring mainly at the particle mterfaces. This results in shrinkage of the sintered compact, which, as previously noted, is more desirable.
  • Sintered parts prepared from the particulate alloys of the described reduction process possess good physical properties even without further treatment.
  • the degree of shrinkage and the resulting strength depend mainly on the copper content, with maximum shrinkage and maximum strength at about 30% copper.
  • a further important feature of the present invention resides in the discovery of a novel heat-treatment process for the alloy powders, which leads to a striking and unprecedented increase in the density and physical strength of the final sintered compact.
  • This heat treatment represents in effect a densification or pre-shrmkage, reducing the degree of shrinkage in the final smtermg step without, however, leading to the undeslrable expansion effect referred to previously.
  • the ot-'y transition temperature of iron lies at about 910 C., but in the case of iron containing over 3.5% copper this transition occurs at about 83 5-850 C. It has been found that heat treatment of the new alloy powders is most effective at a temperature between the oc-'y transition temperature of the iron-rich phase and a temperature about 150 C. lower. The best results are obtained by heat treating at a temperature less than 50 C. below the ot-'y transition, preferably at about 825-845 C. Such conditions lead to development of the highest density, strength and hardness, with minimum shrinkage, upon sintering. Properties begin to drop off abruptly from the optimum when the heat-treatment temperature exceeds 845-850 C.
  • the powder should be heat treated for at least about 30 minutes before cooling.
  • the maximum time is not critical, and periods up to hours may be used. However, there is no advantage to heat treating for more than 4 hours, and the optimum results are generally achieved in about 1-2 hours.
  • the reduced powder subjected to heat treatment contains over 2% oxygen, it is best to heat treat under reducing conditions, so as to further reduce oxygen content below 2% and preferably below 1% during this step. If however, the oxygen content is already 2% or less, an inert atmosphere may be employed if desired.
  • the powders are discharged from the furnace as loosely sintered masses, which quickly cool and may be reground to particles finer than 60-80 mesh in the same manner as after the primary reduction process.
  • A'preliminary insight into the microstructures of the new alloys is provided by their X-ray diffraction patterns.
  • An alloy containing 20% copper displays essentially the same pattern after primary reduction and after heat treatment: both an ot-iron-rich phase and an e-copperrich phase is detected.
  • the diffraction pattern of a 7% copper alloy after heat treatment is substantially similar, except for the expected indication that a lower proportion of the copper-rich phase is present.
  • the 7% alloy after primary reduction exhibits a pattern corresponding to a single a-iron-rich phase. In each of these diagrams, the iron peaks are relatively flattened, the copper peaks sharper.
  • a more accurate insight into the microstructures is gamed by microscopic examination of the alloy particles, mounted, polished, and etched with nitric acid to erode copper-rich areas and thereby delineate the phases.
  • the specimen after reduction displays dispersed copper-rich particles about 350 A. in diameter arranged in clustered bands, with an average distance of about A. between copper particles.
  • the clusters are separated from each other by distances ranging from a little as 500 A. to as great as about 0.75 micron. Between the clusters, copper-rich particles also averaging about 350 A. in diameter are detected, but it is likely that particles smaller than the 50 A. resolution limit are also present. It is likewise possible to detect cracks in the microstructure, about 0.1-0.3 in length by 400-900 A. in width, as well as angular voids 0.1-0.9, in diameter.
  • the cracks are no longer visible, and the clusters now appear in bands or rings about IO tiS in length by 3 i1 in width.
  • the copper particles in these rings are found to average about 400 A. in diameter, with an interparticle spacing of about 150 A. Those copper particles between clusters which are resolved average about A. in diameter, with an interparticle spacing of about 550 A.
  • FIG. 3 illustrates an alloy containing 20% copper, after primary reduction
  • FIG. 4 depicts the same alloys after heat treatment, each enlarged about 3600 diameters.
  • the prominent insular areas which occupy most of the field of view are plateau-like iron grains surrounded by copper-rich valleys eroded by the acid.
  • the iron grains may appear to the eye as depressions, but this apparent stereoscopic reversal is an optical illusion which can be attributed to the lighting.
  • the iron grains are irregular in shape, whereas after heat treatment they have become rounded or spheroidized.
  • cracks are detected in the reduced specimen, about 2500 A. in length and 850 A. in Width. These may account at least in part for the higher shrinkage which occurs upon sintering, and they are absent in the particles after heat treatment.
  • FIG. 4 represents a portion of the field of view of FIG. 4, enlarged about 17,700 diameters.
  • the most prominent feature of the illustration is an elongated valley or copperrich area separating portions of two adjacent iron grains.
  • the pictured area within those iron grains is pitted by erosion of copper-rich particles through the acid treatment, and it is seen that the copper particles within the iron grains fall into two difiYerent size groups: primary particles having a diameter of about 0.1-0.5u, and secondary particles having a diameter less than about 0.05
  • the dispersion of more copper within the iron grains in the alloys of the present invention may account for their higher sintered strength relative to conventionally infiltrated alloys of equivalent density, whose copper content would appear to be more concentrated between the grains.
  • Iron grain length Heat-treated powder [1. Sintered part Conventional infiltration Distance Iron Iron between grain grain iron length width grains Sintered part from heat treated powder, [L 16. 28 14. 00 3. 41 Conventional infiltration 40. 01 22. 6G 12. 51
  • the porosity of sintered iron compacts is ordinarily such that it is necessary to introduce in excess of 10-15% copper for adequate infiltration by conventional technique. Accordingly, for a standard of comparison for the new alloys of low copper content, it is necessary to turn to sintered parts made from blended copper and iron powders.
  • Sintered bars containing 7% copper and prepared from a blend of 100 mesh copper and iron powders when microscopically examined, exhibit large angular pores and massive copper areas 30,11. and more in diameter.
  • the sintered compact prepared from the new particulate alloy containing 7% copper exhibits a very fine, uniform, close-packed structure.
  • the excellent physical properties provided by the new particulate copper-iron alloys can be even further enhanced by various techniques, providing tensile strengths as highas 150,000 p.s.i. For instance, the incorporation .of minor proportions of graphite before'molding and sintering affords increases of from 30,000 to 60,000 p.s.i. in tensile strength. Graphite levels of about 0.5-2% are usually adequate. Re-pressing and re-sintering (coining) operations are also beneficial for increasing density and strength, as are various post treatments, such as quenching, drawing and normalizing, as further illustrated in the examples which follow.
  • the iron mill scale of the above formulation is a byproduct of steel blooming or finishing mills, finer than 325 mesh with about 50% coarser than 20 microns. It has an apparent density of 1.8-2.2 grams per cubic centimeter and an analysis as follows:
  • the cement cop per of the above formulation is a byproduct of mine waste water, finer than 20 microns with about 85% finer than 10 microns. It has an apparent. density of 0.8-1.5 grams per cubic centimeter and an analysis as follows:
  • the ingredients are combined and milled into pellets in amix muller or chaser, which permits intimate admixture with a minimum of grinding action.
  • the resulting pell'ets are charged to a reduction furnace at about 1120- ll35' C. and held atthat temperature in hydrogen or dissociated ammonia-for 45 minutes. After reduction the pellets are removed from'the furnace and broken up, first in a hammer mill to /s inch and smaller, and then in a micropulverizer so that all particles are finer than 80 mesh.
  • the product has an apparent density of 2.3-2.5 .grams per cubic centimeter and an oxygen content of about 1.6% (obtained by reduction in hydrogen at 1050 C. for 30 minutes) or 2.37% (obtained by Leco methodmelting in vacuum at 3500 F.).
  • the hydrogen weight loss reflects only reducible oxygen content.
  • Hematite Fe O or magnetite (Fe O -FeO) in sufficient quantity to provide the same iron content may be substituted for the iron mill scale in the above formulation.
  • pure cuprous oxide may be substituted for the cement copper.
  • carbon monoxide may be substituted for hydrogen, or gases rich in carbon monoxide or hydrogen, such as producer gas, may be used.
  • EXAMPLE 2 -1 AND 2% COPPER ALLOYS Grams Iron mill scale 1314.2 Cupric nitrate trihydrate 37.5 or 76.0 Carboxymethyl cellulose 6.2 Water 300.0
  • cupric nitrate may be replaced by equivalent proportions of cupric oxide and nitric acid, or by an equivalent proportion of cupric acetate.
  • This formulation is pelletized, reduced at 1110 C. and heat-treated as described in Example 1.
  • Equivalent quantities of hematite Fe O and nickelous acetate tetrahydrate may be substituted for the iron mill scale and nickel nitrate.
  • An equivalent proportion of pure cuprous oxide may be substituted for the cement copper.
  • a 20% copper alloy containing 1% molybdenum is prepared from the following ingredients by the reduction and heat treatment procedure of Example 1:
  • a similar alloy containing 1% tungsten is prepared in the same manner, by substituting 12.6 grams of tungstic anhydride. (W0 for the molybdic oxide in the above formulation.
  • An equivalent cobalt content is provided by substituting 14.1 grams of cobaltic oxide (C0 0 for the molybdic oxide.
  • Hematite (Fe O may also be substituted for the iron mill scale by appropriate adjustment in the quantity added.
  • Example 7 The procedure of Example 1A is repeated in a series of batches with the single exception that some of these are reduced at 1000 C. instead of 1120-1135 C. Each of the reduced powders is then compacted at 50 t.s.i. sintered in hydrogen at 1120 C. for minutes, and subjected to physical testing, with results as follows:
  • Example 5 The procedure of Example 1A is repeated with iron mill scales of varying particle size. The resulting reduced powders are compacted at 50 tons per square inch, sintered in hydrogen at 1120 C. for 45 minutes, and subjected to physical testing, with results as follows:
  • EXAMPLE 8 HEAT-TREATMENT EFFECT A quantity of the reduced 7% copper alloy powder prepared in Eaxmple 1A is divided into a number of 150 gram batches for heat treatment as described in Example 13, but the temperatures and periods of heat treatment are varied as outlined below. Each heat-treated powder is compacted and sintered as described in Example 7, and tested with results as follows:
  • the apparent powder densities range from 2.44 to 2.58 g./ cc. and the sintered densities from 6.52 to 6.84 g./cc.
  • Example 1 The procedure of Example 1 is repeated, this time sub- 1 1 B stituting for the cement copper an equivalent proportion 2 8-32 figs- (70 grams) of atomized copper powder finer than 100 2 B5217 mesh. The reduction is conducted at 1000 C. for 45 minutes, with heat treatment at 835 C. for one hour.
  • the reduced and heat-treated powders provide the following properties:
  • EXAMPLE 15 EFFECT OF COMPACTING PRESSURE Heat- Reduced treated A 7% copper alloy powder, prepared by reduction and Tensilemngthyp si 52,400 65,800 e treatment s descrlbed 111 E p l combined Elongation, percent 0.8 1.0 With 0.75% stear1c acid, compacted at various pressures,
  • Example 14 OTHER COPPER SOURCES The procedure of Example 1 is repeated, substituting for the cement copper equivalent quantities in proportion to their copper content of various other copper sources. After reduction at 1125 C. for minutes and heat treatment EXAMPLE 16.GRAPHITE EFFECT WITH VARYING COMPACTING PRESSURES 30 Example 15 is repeated, this time incorporating 1% graphite in each heat-treated powder prior to compacting and sintering, with results as follows:
  • Cupric oxide (83.02% Cu) 6.
  • EXAMPLE 18 EXAMPLE 18.-GIU ⁇ PHITE EFFECT WITH VARYING COPPER CONTENT A series of ferrous allow powders of varying copper content are prepared by the procedures of Examples 1 and 2, with reduction at 1125 C. for 45 minutes followed by heat treatment at 835 C. for one hour in-hydrogen. Each powder is combined with 1% graphite. After press- Perce nt copper:
  • Sintered compacts prepared as in Example 18 are subted to various additional treatments to further enhance 40 physical properties, with results as follows Aged density, g
  • a Particulate alloy as claimed in claim 1 wherein and sintering at 1120 C. for 45 minutes in hydrogen.
  • the iron powder has in excess of about 40 and up to about Sintered Linear Percent density, Percent Tensile Elongation, shrinkage, copper g./cc. porosity X- ,p.s.i. percent percent Hardness 6.
  • 28 20. 4 35. 6 4. 9 50.01) B 25. 5 6 3O 20. 7 0 2. 9 0. 92)
  • B 21. 4 6. 37 20.7 42 1 1.6 (1.88)
  • 45 cles comprise primary particles having an average diame- 1.
  • An alloy in powder form consisting essentially of ter between about 0.1 and 0.5 micron and secondary pariron and 150% by weight of copper characterized by ticles having an average diameter less than about 0.05 iron-rich phase having a highly uniform dispersion of micron. sub-micron copper-rich particles therein, and such that 9.
  • the alloy of claim 8 having a copper content of for copper contents in excess of 10% the micro-structure 50 about 4%. is characterized by iron grains whose average particle 10.
  • the alloy of claim 8 having a copper content of size is less than about 35 microns. about 12%.
  • the alloy of claim 8 having a copper content of the iron powder has from about 1 up to about 6% by about 20%.
  • Weight of copper, said particles providing a tensile References Cited strength of at least about 45,000 pounds per square inch UNITED STATES PATENTS upon pressing at 50 tons per square inch and sintering at 1120 C i h d 2,042,635 6/1936 Schellens 75125 XR 3.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
US471767A 1965-07-13 1965-07-13 Particulate powder of iron with copper contained therein Expired - Lifetime US3489548A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US47176765A 1965-07-13 1965-07-13

Publications (1)

Publication Number Publication Date
US3489548A true US3489548A (en) 1970-01-13

Family

ID=23872917

Family Applications (1)

Application Number Title Priority Date Filing Date
US471767A Expired - Lifetime US3489548A (en) 1965-07-13 1965-07-13 Particulate powder of iron with copper contained therein

Country Status (4)

Country Link
US (1) US3489548A (en。)
BE (1) BE683502A (en。)
GB (1) GB1155366A (en。)
SE (1) SE317521B (en。)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5470373A (en) * 1993-11-15 1995-11-28 The United States Of America As Represented By The Secretary Of The Navy Oxidation resistant copper
WO1996005014A1 (en) * 1994-08-17 1996-02-22 WELLER, Emily, I. Soldering iron tip made from a copper/iron alloy composite
CN103203456A (zh) * 2013-04-15 2013-07-17 河北钢铁股份有限公司邯郸分公司 利用冷轧废酸再生氧化铁红制备铁铜合金的方法
CN113500205A (zh) * 2021-07-11 2021-10-15 吉林大学重庆研究院 一种双金属材料的3d打印方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2042635A (en) * 1932-09-17 1936-06-02 Shellwood Johnson Company Porous metal body and process for making it
US2754194A (en) * 1953-12-29 1956-07-10 Republic Steel Corp Process for making copper-iron powder
US3049421A (en) * 1958-08-27 1962-08-14 Nat Res Corp Production of metals
US3085876A (en) * 1960-03-01 1963-04-16 Du Pont Process for dispersing a refractory metal oxide in another metal

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2042635A (en) * 1932-09-17 1936-06-02 Shellwood Johnson Company Porous metal body and process for making it
US2754194A (en) * 1953-12-29 1956-07-10 Republic Steel Corp Process for making copper-iron powder
US3049421A (en) * 1958-08-27 1962-08-14 Nat Res Corp Production of metals
US3085876A (en) * 1960-03-01 1963-04-16 Du Pont Process for dispersing a refractory metal oxide in another metal

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5470373A (en) * 1993-11-15 1995-11-28 The United States Of America As Represented By The Secretary Of The Navy Oxidation resistant copper
WO1996005014A1 (en) * 1994-08-17 1996-02-22 WELLER, Emily, I. Soldering iron tip made from a copper/iron alloy composite
US5553767A (en) * 1994-08-17 1996-09-10 Donald Fegley Soldering iron tip made from a copper/iron alloy composite
US5579533A (en) * 1994-08-17 1996-11-26 Donald Fegley Method of making a soldering iron tip from a copper/iron alloy composite
CN103203456A (zh) * 2013-04-15 2013-07-17 河北钢铁股份有限公司邯郸分公司 利用冷轧废酸再生氧化铁红制备铁铜合金的方法
CN113500205A (zh) * 2021-07-11 2021-10-15 吉林大学重庆研究院 一种双金属材料的3d打印方法

Also Published As

Publication number Publication date
DE1533353B2 (de) 1972-11-16
SE317521B (en。) 1969-11-17
GB1155366A (en) 1969-06-18
DE1533353A1 (de) 1972-03-23
BE683502A (en。) 1966-12-30

Similar Documents

Publication Publication Date Title
KR20010093762A (ko) 몰리브덴-구리 복합분말
US3307924A (en) Copper infiltrating composition for porous ferruginous material
US3583864A (en) Chemical process of producing an iron-copper alloy powder
US3397057A (en) Method for producing flowable metal powders
US3158473A (en) Method for producing composite bodies
US3368890A (en) Metal powder from cast iron chips
US3888657A (en) Process for production of metal powders having high green strength
US5071473A (en) Uniform coarse tungsten carbide powder and cemented tungsten carbide article and process for producing same
US3850614A (en) Production of tungsten and carbide powder
US3489548A (en) Particulate powder of iron with copper contained therein
US2657129A (en) Aluminum-alloyed corrosion-resistant metal powders and related products and processes
US3515540A (en) Mixed cobalt/tungsten carbide powders
DE2303697B1 (de) Verfahren zur herstellung von legierungspulvern aus seltenen erden und kobalt
US3375109A (en) Process for preparing rheniumrefractory alloys
US4983354A (en) Uniform coarse tungsten carbide powder and cemented tungsten carbide article and process for producing same
White et al. Freeze-dried tungsten heavy alloys
RU2043868C1 (ru) Способ получения спеченных изделий из диффузионно-легированных железных порошков
US2657127A (en) Production of chromium-alloyed corrosion-resistant metal powders and related products
US2656595A (en) Chromium-alloyed corrosion-resist
US3196007A (en) Beryllium copper composition and method of producing green compacts and sintered articles therefrom
US3481714A (en) Flowable metal powders
US3326677A (en) Process of dispersion-hardening of iron-group base metals
US3576619A (en) Method for making alloy powders
US3752712A (en) Iron copper prealloys
Zhu et al. Revealing the powder size-sintering temperature synergistic effect in microstructure transformation of 97 W alloy from extrusion-based additive manufacturing process