US2497540A - Fluxes for the treatment of light alloys - Google Patents

Fluxes for the treatment of light alloys Download PDF

Info

Publication number
US2497540A
US2497540A US770763A US77076347A US2497540A US 2497540 A US2497540 A US 2497540A US 770763 A US770763 A US 770763A US 77076347 A US77076347 A US 77076347A US 2497540 A US2497540 A US 2497540A
Authority
US
United States
Prior art keywords
magnesium
flux
chloride
chlorides
fluxes
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
US770763A
Inventor
Emley Edward Frederick
Junction Clifton
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.)
Magnesium Elektron Ltd
Original Assignee
Magnesium Elektron Ltd
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 Magnesium Elektron Ltd filed Critical Magnesium Elektron Ltd
Application granted granted Critical
Publication of US2497540A publication Critical patent/US2497540A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/10General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents

Definitions

  • invention -relatesto fluxes forthe treatment I of light alloys consisting of -magnesium hbase 'alloys containing rare earth metals, and
  • composition of these fluxes appeared to be very critical in so far as compositions tending to be somewhat fluid showed the pronounced non-wetting effects to be expected in the absence of magnesium chloride, whereas attempts to 55 .20
  • the use of "sdiu.m”'and “potassium* fluoride overcome this-difiiculty by'increasing' the amount or thecalcium fluoride until the "flux" 'was ,:so -viscous- -as-to-be--incapab1e" of "showing non' wettingiJcharacteri ticsmroduced: fluxes'gwhichewere 5 aitoo dry sforesatisfactery.gprotection :of the emetal .tagainst oxidation.
  • magnesium fluoride is substantially insoluble in certain chloride mixtures not containing magnesium chloride and I have used this discovery to make fluxes which are very satisfactory for use with alloys containing rare earth metals. I inspissate such chloride mixtures with magnesium fluoride and because the latter is practically insoluble in the chloride mixtures non-wetting does not arise. Furthermore, when the flux melts the particles of magnesium fluoride are readily wetted and coated with the protective base in which they do not dissolve and the magnesium fluoride is thereby protected from contact with the rare earth metals in the alloy and so does not react therewith.
  • the flux may, however, contain a minor proportion of inspissating agents other than magnesium fluoride. Some small amount of ma nesium chloride may be tolerated in the flux but this should not exceed 2% and is preferably less than 0.5%.
  • a flux suitable for the treatment of the aforesaid light alloys is substantially free from magnesium chloride and consists essentially of at least two chlorides of the alkali metals and alkaline earth metals, other than magnesium, these chlorides in the absence of inspissating agents have a liquidus temperature not greater than 610 C., the flux also containing a sufficient quantity of one or more inspissating agents to enable the flux to provide a pasty viscous covering on the molten metal, and at least 75% of the inspissating agents consisting of magnesium fluoride.
  • potassium, and sodium chlorides are suitable for inspissation by magnesium fluoride especially in the following percentages of the chloride mixture(s) Per cent Calcium chloride 40-70 Potassium chloride 6-30 Sodium chloride Q. 24-40 Examples of inspissated flux compositions which we have found satisfactory are as follows:
  • Magnesium base alloys containing one or more rare earth metals can be treated with fluxes made in accordance with the invention with regular production of finished alloys having at least equal freedom from traces of chloride contamina- 4 tion as commonly produced magnesium base alloys containing aluminium.
  • An inspissated flux suitable for the treatment of magnesium alloys-containing-a rare earth metal, which flux is substantially free'from magnesium chloride and consists of at least two chlorides of the alkali metals and alkaline earth metals, other than magnesium, which chlorides when in mixture alone have a liquidus temperature not greater than 610 C., the balance of the flux being a quantity of inspissating agent such as to provide a pasty viscous covering on the molten metal, and at least of the inspissating agent consisting of magnesium fluoride, the quantity of magnesium fluoride being about 20% by weight of the flux.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Description

Patented Feb. 14, 1950 '"Manchester;England, as'signorto Magnesium Elektron LimitedgLondon, England, a British company NdjDrawing. v.;.App1mamma ,am.26,.misz semi No: 7.1!],763. 'iIn'Great BritainAygu'st;29; l946 12 .Claims.
invention -relatesto fluxes forthe treatment I of light alloys consisting of -magnesium hbase 'alloys containing rare earth metals, and
tains substantially no magnesium chloride. {For dthis :purpose I haveendeavoured to develop a =flux which -contains .a :mixture of 'chlorides .-(which'3[s.term..aflprotectivevbase) having-a sufiiciently low melting pointe-to-eenable the flux to prevent burning of the metal'and to provide,
together with a suflicientlquantity of inspissating ia entsutor enable ..th8ifll=.1Xf.t0l':h&Ve the required iscosityrrawpastyviscous; coverin on ithebmetal. c- -lna.ctherawordslhavazendeavoured toi inspissate a mixture ..of .chlorides .-.not,.containing magnesium chloride in a manner in which it has .;previouslyabeenuproposed':to.einspissate.zchloride mixtures consisting largely ofsmagne'siumachldride. I have, however, found that the inspissation of chloride mixtures not containing magnesium chloride is accompanied by certain difiiculties. For example, attempts to inspissate a chloride mixture solely by means of an addition of magnesia, result in a tendency to liquation and dry top-effects, that is to say the flux cover on top of the molten metal is too dry near to its upper surface, and appears to consist mainly of magnesia insufficiently wetted by the chlorides. These difficulties are apparently due to the poor wetting capacity for MgO of chloride mixtures not containing magnesium chloride.
These difficulties can be overcome by prefusing the magnesia with the chloride mixture but this results in a flux, the composition of which must be adjusted somewhat critically to achieve the required degree of inspissation, and which is barely satisfactory in its ability to extinguish burning magnesium.
Accordingly I have attempted to inspissate these chloride mixtures with calcium fluoride.
The composition of these fluxes appeared to be very critical in so far as compositions tending to be somewhat fluid showed the pronounced non-wetting effects to be expected in the absence of magnesium chloride, whereas attempts to 55 .20 The use of "sdiu.m"'and "potassium* fluoride overcome this-difiiculty by'increasing' the amount or thecalcium fluoride until the "flux" 'was ,:so -viscous- -as-to-be--incapab1e" of "showing non' wettingiJcharacteri ticsmroduced: fluxes'gwhichewere 5 aitoo dry sforesatisfactery.gprotection :of the emetal .tagainst oxidation. 'flihetxrange of composition abetween, fluxes-showing qthe non-wetting attendency and-thoser whiohaarentoo; dry. isx-itooz narrow .iorasatisfactory :rcom-mercial. productiona: of-; such lfluxes-eand moreover tdzhe ipptimum .a.calcium s fluoride; acontent rvariestwith temperature of, the ametalv zunderet-reatment.
Attempts to use-.;calcium :fluoridel andimagnesia atg ether ;;save efiuxes gqpOSSessihg -to vsome extent ethe r-disadvantages 1:. associated with sthe separate use ofv both these inspissating agents.
"The -use of ;:strontium and "barium fluorides also produced disadvantages'similar to"thosei.ac-
companying the use'of'calcium fluoride.
gives rise; to introduction of "small amountsfof sodium and traces "of-potassiumintothe'metal nbqth sofewlhichuaiieimbjefltmnablajn addition to non-wetting difficulties.
The us of nma'gnesium ilfiuoride 'was :zinitially QQQXlSldBI'Bd 1impractitable; not 'onlyv-beca-use ituis sine-re. costly l-than-sanyeof ,"lihe fluorides :above .e-mentioned; abut more particularly: because it .:-is
- ..well-:.known that rqmagnesi-um v fluoride will react with the rare earth metals in the same way as magnesium chloride.
I have now made the surprising discovery that unlike the fluorides of sodium, potassium, calcium, strontium, or barium, magnesium fluoride is substantially insoluble in certain chloride mixtures not containing magnesium chloride and I have used this discovery to make fluxes which are very satisfactory for use with alloys containing rare earth metals. I inspissate such chloride mixtures with magnesium fluoride and because the latter is practically insoluble in the chloride mixtures non-wetting does not arise. Furthermore, when the flux melts the particles of magnesium fluoride are readily wetted and coated with the protective base in which they do not dissolve and the magnesium fluoride is thereby protected from contact with the rare earth metals in the alloy and so does not react therewith.
The flux may, however, contain a minor proportion of inspissating agents other than magnesium fluoride. Some small amount of ma nesium chloride may be tolerated in the flux but this should not exceed 2% and is preferably less than 0.5%.
According to the present invention therefore,
a flux suitable for the treatment of the aforesaid light alloys is substantially free from magnesium chloride and consists essentially of at least two chlorides of the alkali metals and alkaline earth metals, other than magnesium, these chlorides in the absence of inspissating agents have a liquidus temperature not greater than 610 C., the flux also containing a sufficient quantity of one or more inspissating agents to enable the flux to provide a pasty viscous covering on the molten metal, and at least 75% of the inspissating agents consisting of magnesium fluoride.
I find in particular that mixtures of calcium,
potassium, and sodium chlorides are suitable for inspissation by magnesium fluoride especially in the following percentages of the chloride mixture(s) Per cent Calcium chloride 40-70 Potassium chloride 6-30 Sodium chloride Q. 24-40 Examples of inspissated flux compositions which we have found satisfactory are as follows:
CaClz 41 25.5 49 NaCl 26 23.5 KCl 9 47 BaClz 7 .5 SIC12 7.5 MgFz 24 20 20 In these examples the figures indicate percentages by weight of th compositions.
Magnesium base alloys containing one or more rare earth metals can be treated with fluxes made in accordance with the invention with regular production of finished alloys having at least equal freedom from traces of chloride contamina- 4 tion as commonly produced magnesium base alloys containing aluminium.
I claim:
1. An inspissated fluxsuitable for the treatment of magnesium alloys-containing-a rare earth metal, which flux is substantially free'from magnesium chloride and consists of at least two chlorides of the alkali metals and alkaline earth metals, other than magnesium, which chlorides when in mixture alone have a liquidus temperature not greater than 610 C., the balance of the flux being a quantity of inspissating agent such as to provide a pasty viscous covering on the molten metal, and at least of the inspissating agent consisting of magnesium fluoride, the quantity of magnesium fluoride being about 20% by weight of the flux.
2. A flux as claimed in claim 1 wherein the chlorides consist of the chlorides of calcium, po-
tassium and sodium, in the following percentages of the total chloride mixture:
Per cent Calcium chloride 40-70 Potassium chloride 6-30 Sodium chloride 24-40 EDWARD FREDERICK EMLEY.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,121,292 Haughton et a1. June 21, 1938 2,327,065 Reimers Aug. 17, 1943 2,396,604. Reimers Mar. 12, 1946 FOREIGN PATENTS I Number Country Date 342,586 Great Britain Feb. 5, 1931 403,891 Great Britain Jan. 4, 1934 489,700 Great Britain Aug. 6, 1938 OTHER REFERENCES Marande, Materials and Methods, February 1946, pp. 418-424.

Claims (1)

1. AN INSPISSATED FLUX SUITABLE FOR THE TREATMENT OF MAGNESIUM ALLOYS CONTAINING A RARE EARTH METAL, WHICH FLUX IS SUBSTANTIALLY FREE FROM MAGNESIUM CHLORIDE AND CONSISTS OF AT LEAST TWO CHLORIDES OF THE ALKALI METALS AND ALKALINE EARTH METALS, OTHER THAN MAGNESIUM, WHICH CHLORIDES WHEN IN MIXTURE ALONE HAVE A LIQUIDUS TEMPERATURE NOT GREATER THAN 610*C., THE BALANCE OF THE FLUX BEING A QUANTITY OF INSPISSATING AGENT SUCH AS TO PROVIDE A PASTY VISCOUS COVERING ON THE MOLTEN METAL, AND AT LEAST 75% OF THE INSPISSATING AGENT CONSISTING OF MAGNESIUM FLUORIDE, THE QUANTITY OF MAGNESIUM FLUORIDE BEING ABOUT 20% BY WEIGHT OF THE FLUX.
US770763A 1946-08-29 1947-08-26 Fluxes for the treatment of light alloys Expired - Lifetime US2497540A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2497540X 1946-08-29

Publications (1)

Publication Number Publication Date
US2497540A true US2497540A (en) 1950-02-14

Family

ID=10908426

Family Applications (1)

Application Number Title Priority Date Filing Date
US770763A Expired - Lifetime US2497540A (en) 1946-08-29 1947-08-26 Fluxes for the treatment of light alloys

Country Status (1)

Country Link
US (1) US2497540A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2797990A (en) * 1953-03-12 1957-07-02 Dominion Magnesium Ltd Flux for magnesium alloys containing zirconium
US3167425A (en) * 1960-04-29 1965-01-26 Magnesium Elektron Ltd Method of producing a magnesium base alloy
US20100307293A1 (en) * 2009-06-08 2010-12-09 Pyrotek Inc. Use of a binary salt flux of nacl and mgcl2 for the purification of aluminium or aluminium alloys, and method thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB342586A (en) * 1929-04-15 1931-02-05 I.G. Farbenindustrie Aktiengesellschaft
GB403891A (en) * 1932-08-03 1934-01-04 Dow Chemical Co Improvements in melting and purifying magnesium and magnesium alloys
US2121292A (en) * 1936-05-05 1938-06-21 Haughton John Leslie Magnesium alloys containing cerium and other elements
GB489700A (en) * 1936-01-06 1938-08-02 Produits Chim Terres Rares Soc Improvements relating to the melting and refining of magnesium and its alloys
US2327065A (en) * 1941-08-30 1943-08-17 Dow Chemical Co Welding flux for magnesium base alloys
US2396604A (en) * 1942-11-21 1946-03-12 Dow Chemical Co Welding flux for magnesium alloys

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB342586A (en) * 1929-04-15 1931-02-05 I.G. Farbenindustrie Aktiengesellschaft
GB403891A (en) * 1932-08-03 1934-01-04 Dow Chemical Co Improvements in melting and purifying magnesium and magnesium alloys
GB489700A (en) * 1936-01-06 1938-08-02 Produits Chim Terres Rares Soc Improvements relating to the melting and refining of magnesium and its alloys
US2121292A (en) * 1936-05-05 1938-06-21 Haughton John Leslie Magnesium alloys containing cerium and other elements
US2327065A (en) * 1941-08-30 1943-08-17 Dow Chemical Co Welding flux for magnesium base alloys
US2396604A (en) * 1942-11-21 1946-03-12 Dow Chemical Co Welding flux for magnesium alloys

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2797990A (en) * 1953-03-12 1957-07-02 Dominion Magnesium Ltd Flux for magnesium alloys containing zirconium
US3167425A (en) * 1960-04-29 1965-01-26 Magnesium Elektron Ltd Method of producing a magnesium base alloy
US20100307293A1 (en) * 2009-06-08 2010-12-09 Pyrotek Inc. Use of a binary salt flux of nacl and mgcl2 for the purification of aluminium or aluminium alloys, and method thereof
US7988763B2 (en) 2009-06-08 2011-08-02 Pyrotek Inc. Use of a binary salt flux of NaCl and MgCl2 for the purification of aluminium or aluminium alloys, and method thereof

Similar Documents

Publication Publication Date Title
GB1252741A (en)
US2848321A (en) Drossing fluxes
US2497540A (en) Fluxes for the treatment of light alloys
US2654670A (en) Flux for treating aluminum and aluminum alloys
US2170863A (en) Process for melting up light metal scrap
US2310231A (en) Brazing solder
US3748121A (en) Treatment of molten ferrous metals
US2261906A (en) Method of alloying magnesium with manganese
US2261905A (en) Method of alloying magnesium with manganese
US2604394A (en) Magnesium base alloys
US2266122A (en) Silicon alloy
US2497539A (en) Process and flux for the treatment of light metals
US1916496A (en) Method of making lead alloys
US2452914A (en) Process and composition for producing magnesium-zirconium alloys
US2497537A (en) Zirconium carrying alloying substance
US2296196A (en) Process for purifying metals
US2464925A (en) Welding flux
US2497538A (en) Fluxes for use in the treatment of light metals
US1698647A (en) Purification of magnesium and its alloys
US3186881A (en) Aluminum flux
US2497529A (en) Process for production of magnesium base alloys containing zirconium
US2686946A (en) Refining beryllium in the presence of a flux
US2706679A (en) Lithium halide flux for treating magnesium-lithium alloys
US2372563A (en) Fluxes for use in the treatment of light metals
US2290296A (en) Process for preparing lead alloys