US3802867A - Procedure for producing structures with globular primary crystals - Google Patents
Procedure for producing structures with globular primary crystals Download PDFInfo
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- US3802867A US3802867A US00219098A US21909872A US3802867A US 3802867 A US3802867 A US 3802867A US 00219098 A US00219098 A US 00219098A US 21909872 A US21909872 A US 21909872A US 3802867 A US3802867 A US 3802867A
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- alloy
- temperature
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- globular
- primary crystals
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Links
- 238000000034 method Methods 0.000 title claims description 19
- 239000013078 crystal Substances 0.000 title abstract description 14
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 24
- 239000000956 alloy Substances 0.000 claims abstract description 24
- 229910002056 binary alloy Inorganic materials 0.000 claims description 4
- 230000005496 eutectics Effects 0.000 description 8
- 239000010453 quartz Substances 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- 239000000155 melt Substances 0.000 description 6
- 238000000137 annealing Methods 0.000 description 5
- 230000008014 freezing Effects 0.000 description 5
- 238000007710 freezing Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- 229910000805 Pig iron Inorganic materials 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 238000010587 phase diagram Methods 0.000 description 2
- 229910001339 C alloy Inorganic materials 0.000 description 1
- 102000020897 Formins Human genes 0.000 description 1
- 108091022623 Formins Proteins 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000010420 art technique Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 230000001376 precipitating effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/10—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of nickel or cobalt or alloys based thereon
-
- 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
- C22C1/02—Making non-ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C19/00—Alloys based on nickel or cobalt
- C22C19/07—Alloys based on nickel or cobalt based on cobalt
Definitions
- G/V m/D (C C,,,) is established in the melt in front of the freezing surface, wherein G, V, m, D, C p and C are as defined herein below.
- the present invention relates to a method for producing globular primary crystals in alloys of the type composed of at least two components, which are at most only mutually soluble in the solid state to a very limited degree, and in which one of the components ordinarily solidifies in faceted form, and wherein the concentrations of the alloy components are between the eutectic concentration and the concentrations corresponding to the maximum solubility.
- FIG. I is a phase diagram of a binary or pseudobinary alloy consisting of components A and B;
- FIG. 2 is a schematic diagram of a suitable annealing device, usable with this invention.
- FIGS. 3, 4 and 5 are metallographic micrographs showing an example of a workpiece according to the present invention.
- FIG. I The phase diagram shown in FIG. I is of the type further described in W. Koster, et al., Archives of the Metallurgy oflron, (Archiv fur Eisenhuttenhus) Vol. 26 (1955) pp. 555-559 and as described in F. D. Lemkey. Metallurgical Transactions 1 (1970) 2,799-2,806.
- component A in the solid state is soluble in component B up to a maximum concentration C while component B in the solid state is soluble in component A up to a maximum concentration C
- the eutectic concentration is denoted C in the diagram.
- the freezing temperature range is denoted AT in the hypoeutectic region and AT in the hypereutectic region.
- Components A and B must be selected as regards quality and quantity in such a waY that the concentration lies between the eutectic concentration C and the concentrations of maximum solubility in the solid state C A or C and such that the primary precipitating crystals solidify in facetted form.
- the workpiece is heated to a temperature in the range of AT, or AT and then slowly cooled.
- the workpiece l is positioned in a double-walled quartz envelope and fixed at support-points 3 and 4 which are rigid with respect to the envelope.
- the wall of the envelope is water-cooled.
- the quartz envelope 2 is closed by a cover 5 having a connection 6 through which a protective gas, preferably argon, can be fed into the interior of the quartz envelope 2.
- Envelope 2 is also arranged to move along the longitudinal axis within an electrically heated resistance coil 7.
- the workpiece 1, together with quartz envelope 2 is drawn at velocity V through coil 7 and thus locally heated to a temperature within the range AT, or AT,,.
- temperature T within the temperature range AT or AT or by varying the velocity V, it is possible to alter the geometric dimensions of the globular primary crystals formed.
- Velocity V must be so chosen that in the cooling phase a temperature gradient G according to the relationship becoming established.
- the symbols 6, V, m, D, C, and C, are as defined above.
- Alloys which are treatable by the methods of this invention include the quasi-binary alloys Co, Cr, Cr Co C wherein the range of X 0.6 to 1.6 or of the type Me,,Cr- Cr Me C wherein Me represents the elements nickel, iron, cobalt or manganese, and particularly nickel or iron.
- the heating zone has a length of between 0.5 and 2.5 cm and the velocity is between 2 and 7 cm per hour.
- FIG. 4 shows the fine globular structure obtained by annealing at at 1,350 C.
- FIG. 3 shows the coarse globular structure obtained by annealing at 1,400-C.
- a process for producing globular primary crystals in an alloy containing at least two components, at least one of which solidifies in facetted form, and which in the solid state are mutually soluble to at most a limited degree, and wherein the concentration of the alloy components is between the eutectic concentration and the concentration corresponding to the solubility maxima which comprises continuously moving a workpiece of an alloy through an elevated temperature zone wherein said workpiece is heated to a temperature between the solidus and liquidus temperatures of the alloy, and then continuously moving said workpiece out of said elevated temperature zone, and cooling said workpiece so that a freezing surface is established in front of the melt and wherein the velocity (V) of the movement of the workpiece through the elevated temperature zone, and the temperature gradient G established in themelt in front of the freezing suface are controlled by the relationship wherein m is the rate of rise in temperature of the liquid phase of the melt, D is the diffusion coefficient, C is the concentration of one constituent of the eutectic in the eutectic composition, and C is the concentration of the
- hypereutectic alloy is the quasi-binary alloy (Co Cr 48 percent vol. (Cr Co C 52 percent vol.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
Globular primary crystals are formed in an alloy by passing the alloy through a temperature zone between the liquidus and solidus temperatures at a velocity such that a temperature gradient G described by the relationship:
Description
United States Patent Sahm Apr. 9, 1974 PROCEDURE FOR PRODUCING 3.542.541 11/1970 Lemkey 75/134 P STRUCTURES WITH GLOBULAR PRIMARY 3,552,953 l/l97l Lemkey et al. 75/l76 X 3,564,940 2/1971 7 Thompson et al. 75/171 [75] Inventor: Peter Sahm, Nussbaumen,
Switzerland [73] Assignee: BBC Brown, Boveri & Company,
Limited, Baden, Switzerland [22] Filed: Jan. 19, 1972 [21] Appl. No.: 219,098
[30] Foreign Application Priority Data Jan. 21, l97l Switzerland 970/71 [52] US. Cl. 75/65 ZM [51] Int. Cl C22b 9/02 [58] Field of Search. 75/65 ZM, 135, 134 R, I34 F, 75/ I76, 171
[56] References Cited UNITED STATES PATENTS 2,938,820 5/1960 Turner 148/134 Ar 6 l CRYSTALS Primary E.\'aminerL. Dewayne Rutledge Assistant E.\'aminerM. .I. Andrews Attorney, Agent, or Firm0blon, Fisher, Spivak, Mc- Clelland & Maier [57] ABSTRACT Globular primary crystals are formed in an alloy by passing the alloy through a temperature zone between the liquidus and solidus temperatures at a velocity such that a temperature gradient G described by the relationship:
G/V m/D (C C,,,) is established in the melt in front of the freezing surface, wherein G, V, m, D, C p and C are as defined herein below.
7 Claims, 5 Drawing Figures SHEET 1 [1F 3 PATENTEU APR 9 I974 SHEET 3 BF 3 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing globular primary crystals in alloys of the type composed of at least two components, which are at most only mutually soluble in the solid state to a very limited degree, and in which one of the components ordinarily solidifies in faceted form, and wherein the concentrations of the alloy components are between the eutectic concentration and the concentrations corresponding to the maximum solubility.
2. Description of the Prior Art Globular solidification of primary crystals, i.e., approximately spherically shaped crystals which first separate out of the melt, have been attained with alloys of this type by melting techniques or by annealing below the eutectic or eutectoid temperature. In the latter method, one component is precipitated in lamellar form and is caused to coagulate. Neither of these prior art techniques however, have been completely satisfactory for all industrial applications.
When the primary crystals solidify from the alloy melt in faceted form, i.e., bevel-edged crystals, the working tool resulting therefrom will be considerably more brittle than if this component is solidified in a globular form. In fact, it is well known that spherical graphite pig iron has a considerably higher ductility than lamellar graphite pig iron.
New methods for preparing workpieces having globular primary crystals therefore have been sought.
SUMMARY OF THE INVENTION is established in the melt in front of the freezing surface.
In the above relationship:
G temperature gradient V velocity or speed of movement of the alloy work- 1 piece through the elevated temperature zone m rate of liquidus temperature rise C alloy composition D diffusion coefficient C. eutectic composition BRIEF DESCRIPTION OF THE DRAWINGS The invention will further be explained by reference to the drawings and photomicrographs, designated as FIGS. 1 through 3 in which:
FIG. I is a phase diagram of a binary or pseudobinary alloy consisting of components A and B;
FIG. 2 is a schematic diagram of a suitable annealing device, usable with this invention; and,
FIGS. 3, 4 and 5 are metallographic micrographs showing an example of a workpiece according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The phase diagram shown in FIG. I is of the type further described in W. Koster, et al., Archives of the Metallurgy oflron, (Archiv fur Eisenhuttenwesen) Vol. 26 (1955) pp. 555-559 and as described in F. D. Lemkey. Metallurgical Transactions 1 (1970) 2,799-2,806.
In the case of the eutectically solidifying alloy A-B in FIG. 1, component A in the solid state is soluble in component B up to a maximum concentration C while component B in the solid state is soluble in component A up to a maximum concentration C The eutectic concentration is denoted C in the diagram. The freezing temperature range is denoted AT in the hypoeutectic region and AT in the hypereutectic region. Components A and B must be selected as regards quality and quantity in such a waY that the concentration lies between the eutectic concentration C and the concentrations of maximum solubility in the solid state C A or C and such that the primary precipitating crystals solidify in facetted form. To change the structure at the selected part ofa workpiece consisting of an alloy A-B, the composition of which lies between the concentrations C C,. or C C n, the workpiece is heated to a temperature in the range of AT, or AT and then slowly cooled.'For this purpose, as shown in FIG. 2, the workpiece l is positioned in a double-walled quartz envelope and fixed at support- points 3 and 4 which are rigid with respect to the envelope. The wall of the envelope is water-cooled. The quartz envelope 2 is closed by a cover 5 having a connection 6 through which a protective gas, preferably argon, can be fed into the interior of the quartz envelope 2. Envelope 2 is also arranged to move along the longitudinal axis within an electrically heated resistance coil 7. The workpiece 1, together with quartz envelope 2 is drawn at velocity V through coil 7 and thus locally heated to a temperature within the range AT, or AT,,. By suitably selecting temperature Twithin the temperature range AT or AT or by varying the velocity V, it is possible to alter the geometric dimensions of the globular primary crystals formed. Velocity V must be so chosen that in the cooling phase a temperature gradient G according to the relationship becoming established. The symbols 6, V, m, D, C, and C, are as defined above.
Alloys which are treatable by the methods of this invention include the quasi-binary alloys Co, Cr, Cr Co C wherein the range of X 0.6 to 1.6 or of the type Me,,Cr- Cr Me C wherein Me represents the elements nickel, iron, cobalt or manganese, and particularly nickel or iron.
In one embodiment, the heating zone has a length of between 0.5 and 2.5 cm and the velocity is between 2 and 7 cm per hour.
Having generally described the invention a further understanding can be attained by reference to the following specific example which is presented for purposes of illustration only and is not intended to be limiting unless otherwise specified.
EXAMPLE To produce a rod-shaped workpiece of a quasi-binary alloy (Co Cr,, 48 percent vol. (Cr Co C 52 percent vol., 40.22 percent wt Co, 54.78 percent wt Cr and 5 percent wt C were melted in a A1 0 crucible and held for min at a temperature of 1,50() C. The melt was then drawn into a quartz tube. After cooling, the rod (workpiece), which had solidified in the quartz tube, was cleaned by etching for /2 hour in hydrofluoric acid to remove adhering Si 0 The workpiece was then brought to the annealing device described with reference to FIG. 2. The workpiece was drawn at a velocity of 7 cm/h through resistance coil 7 which has a heating zone 1.5 cm long. In a first experiment the temperature in the workpiece on passing through the heating zone was approximately 1,350 C. The temperature gradient was 50 C/cm or less. The irregular structure of the workpiece cooled from the molten state in the quartz tube can be seen in FIG. 5. FIG. 4 shows the fine globular structure obtained by annealing at at 1,350 C. FIG. 3 shows the coarse globular structure obtained by annealing at 1,400-C.
ln this example:
G 50 C/cm or less (S 30 Vol. percent C 52 Vol. percent A oJ 'iLa) B s.2 o.s a)
Having now fully described the invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention. Accordingly,
What is new and desired to be secured by letters patent is:
l. A process for producing globular primary crystals in an alloy containing at least two components, at least one of which solidifies in facetted form, and which in the solid state are mutually soluble to at most a limited degree, and wherein the concentration of the alloy components is between the eutectic concentration and the concentration corresponding to the solubility maxima, which comprises continuously moving a workpiece of an alloy through an elevated temperature zone wherein said workpiece is heated to a temperature between the solidus and liquidus temperatures of the alloy, and then continuously moving said workpiece out of said elevated temperature zone, and cooling said workpiece so that a freezing surface is established in front of the melt and wherein the velocity (V) of the movement of the workpiece through the elevated temperature zone, and the temperature gradient G established in themelt in front of the freezing suface are controlled by the relationship wherein m is the rate of rise in temperature of the liquid phase of the melt, D is the diffusion coefficient, C is the concentration of one constituent of the eutectic in the eutectic composition, and C is the concentration of the corresponding constituent in the alloy composition of the workpiece being treated, thereby producing globular primary crystals.
2. The process of claim 1 wherein the'alloy used is a hypereutectic alloy.
3. The process of claim 2 wherein said hypereutectic alloy is the quasi-binary alloy (Co Cr 48 percent vol. (Cr Co C 52 percent vol.
4. The process of claim 3 wherein the approximate length of the elevated temperature zone is 0.5 2.5 cm.
5. The process of claim 3 wherein the temperature is at least l,350 C.
6. The process of claim 5 wherein the temperature is 1',400 C.
7. The process of claim 1 wherein the velocity is between 2 and 7 cm per hour.
Claims (6)
- 2. The process of claim 1 wherein the alloy used is a hypereutectic alloy.
- 3. The process of claim 2 wherein said hypereutectic alloy is the quasi-binary alloy (Co0.7Cr0.3) 48 percent vol. -(Cr6.2Co0.8C3) 52 percent vol.
- 4. The process of claim 3 wherein the approximate length of the elevated temperature zone is 0.5 - 2.5 cm.
- 5. The process of claim 3 wherein the temperature is at least 1, 350* C.
- 6. The process of claim 5 wherein the temperature is 1,400* C.
- 7. The process of claim 1 wherein the velocity is between 2 and 7 cm per hour.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH97071A CH543594A (en) | 1971-01-21 | 1971-01-21 | Process for the production of structures with globular primary crystals |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3802867A true US3802867A (en) | 1974-04-09 |
Family
ID=4199430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US00219098A Expired - Lifetime US3802867A (en) | 1971-01-21 | 1972-01-19 | Procedure for producing structures with globular primary crystals |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US3802867A (en) |
| CH (1) | CH543594A (en) |
| DE (1) | DE2112394A1 (en) |
| FR (1) | FR2122974A5 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5398483A (en) * | 1993-01-29 | 1995-03-21 | Polymers Reconstructive A/S | Method and apparatus for packaging, mixing and delivering bone cement |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH654593A5 (en) * | 1983-09-28 | 1986-02-28 | Bbc Brown Boveri & Cie | METHOD FOR PRODUCING A FINE-GRAIN WORKPIECE FROM A NICKEL-BASED SUPER ALLOY. |
-
1971
- 1971-01-21 CH CH97071A patent/CH543594A/en not_active IP Right Cessation
- 1971-03-15 DE DE19712112394 patent/DE2112394A1/en active Pending
-
1972
- 1972-01-19 US US00219098A patent/US3802867A/en not_active Expired - Lifetime
- 1972-01-19 FR FR7201798A patent/FR2122974A5/fr not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5398483A (en) * | 1993-01-29 | 1995-03-21 | Polymers Reconstructive A/S | Method and apparatus for packaging, mixing and delivering bone cement |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2122974A5 (en) | 1972-09-01 |
| CH543594A (en) | 1973-10-31 |
| DE2112394A1 (en) | 1972-08-03 |
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