CA1120728A - Preparation of phosphorus-containing metallic glass-forming alloy melts - Google Patents
Preparation of phosphorus-containing metallic glass-forming alloy meltsInfo
- Publication number
- CA1120728A CA1120728A CA000331545A CA331545A CA1120728A CA 1120728 A CA1120728 A CA 1120728A CA 000331545 A CA000331545 A CA 000331545A CA 331545 A CA331545 A CA 331545A CA 1120728 A CA1120728 A CA 1120728A
- Authority
- CA
- Canada
- Prior art keywords
- phosphorus
- flux
- alloy
- percent
- weight
- 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
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/10—General 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
Abstract
ABSTRACT
Phosphorus rich transition metal alloys are pro-tected by a layer of boron oxide during the melting pro-cess. The presence of the boron oxide layer prevents the evaporation of phosphorus values. Melting of phosphorus-containing iron/nickel/cobalt based glass-forming alloys under a refining metal oxide/boron trioxide flux reduces undesirable metal oxide impurities, such as titanium dio-xide impurities, prevents oxidation of the melt, and re-duces loss of phosphorus values from the melt.
Phosphorus rich transition metal alloys are pro-tected by a layer of boron oxide during the melting pro-cess. The presence of the boron oxide layer prevents the evaporation of phosphorus values. Melting of phosphorus-containing iron/nickel/cobalt based glass-forming alloys under a refining metal oxide/boron trioxide flux reduces undesirable metal oxide impurities, such as titanium dio-xide impurities, prevents oxidation of the melt, and re-duces loss of phosphorus values from the melt.
Description
PREPARATION OF PHOSPHOR~S-CONTAINING METAhLIC
GL~SS-FO~I~NG ~LOY MEL1'S
. . ~
BACKGROU~D OF TH~ INVENTION
... .
Recent advances in the metallurgical ar.s in-clude development of alloys which, ~ihen rapidly quench-ed from the melt at rates in excess of about 104 to 106C
per second, form glassy ~amorphous) solids. Such glass-forming alloys commonly are based on transition metals, usually iron, nickel and/or cobalt, in conjunction with one or more metalloids of phosphorus, boron and carbon.
- Glass-forming alloys are, for examplel described in U.S.
Pat. 3,856,513 issued December 24, 1974 to Chen et al.
Preparation of phosphide based melts of glass-formin~ alloys under ambient atmosphere leads to oxide inclusions in the glassy metal product. The conventional method of excluding the ambient atmosphere by vacuum melting leads to possible losses of phosphorus values from the melt due to evaporation-. Iron phosphide is a basic ingredient in many glass-forming metallic alloy compositions, and in the high purity form required for such purpose, it is quite costly. Inexpensive forms of iron phosphide available are impure and contain phosphorus in form which can evaporate upon heatin~, and which tends to form volatile phosphorus pentoxide, and which poses a safety hazard and results in changes of the alloy compo-sition. Glassy solid structures are obtained from such alloys by processes such as the melt spin process wherein a fine jet o~ the molten alloy is impinc3ed upon a rapidly movinc~ chill surface for solidification. Orifice dia-meters in this process are exceedingly s~nall, and orifice "
,~.
;fz~3 .
pluggage on account of solid impurities contained in the melt can represent seri~us problems. Iron, cobalt or niekel based phosphorus-containing glass-forming alloys whieh additionally contain boron as a metalloid are particularly prone to contamination with solid partieles.
In such alloy, these particles were found to be pre-dominantly small partieles of TiO2 and/or TiBo3, both of whieh have high melt points, and both of whieh are rela-tively insoluble in the melt. It was ~ound that titanium is an impurity commonly contained in ferrophosphorus, which is used as a source of phosphorus in making these alloys, although titanium may also be present as contami-nant in other raw materials employed in making these alloys.
The present invention provides refining flux for redueing oxidation of and loss of phosphorus values from phosphorus-containing alloys, espeeially phosphorus-eon-taining iron, niekel and~or cobalt-based alloys.
- SVMM~RY OF THE INVENTIO~
Phosphorus-containing metallic glass-forming alloy melts are covered with a layer o~ molten boron tri-oxide flux. Such layer protects the melt from oxidation, dissolves oxide partieulates and impurities from the molten metal alloy and prevents the evaporation of p~os-phorus values. The flux floating on the alloy melt will not interfere with subsequent easting or spinning opera-tions, and the alloy melt can be replenished direetly through the flux layer. Alloys prepared according to the process of the present invention leave minimum residues in the jetting crucible in subsequent melt spin operations~
Phosphorus-containing iron, nickel and/or cobalt-based alloys are desirably melted under a boron trioxide flux additionally comprising oxides o iron, niekel and/or eobalt. The ~lux layer protects the molten alloy from oxidationt reduces or eliminates contamination of the melt with particulate matter, especially metal oxides, and pre-vents loss of phospllorus values by vaporization.
'' ` ! ' -'; ;~ ~
DETAILED ~ESCRIPTION OF THE INVENTION
.
Metallic glass-formin~ alloys which benefit from protection by boron trioxide flux contain phosphorus as a metalloid component, alone or together with other metalloids, such as boron, ca:rbon and silicon. The phosphorus component of such alloys is usually contributed by ingredients having the formulas FePx, NiPX, CoPx, MnPx, wherein x is between abut 0.3 and 1.1 and preferably bet-ween about 0.5 and 1. Preferred alloy compositions include alloys utilizing as source of phosphorus FePx wherein x is between about 0.5 and 1. Pre:Eerred allo.y compositions in-clude transition metal alloys containing between about 3 - and 25 weight percent phosphorus. These alloys have a phosphorus partial pressure of less than 20 micron, and melting points of between about 900C and 1200C.
Phosphorus-containing alloys based on one or more of iron~ nickel and/or cobalt which benefit from melting under the refining boron trioxide flux which additionally contains oxides of iron, nickel and/or cobalt have the general formula MaPbYC wherein M is a metal se-lected from one or more of the group consisting of iron, cobalt and nickel; P represents phosphorus; Y represents a metalloid selected from one or both of the group con-sisting of boron and carbon; and a, b and c are in atomic percent, wherein a is about 70 to 90, b is 0-20, but desirably at least 1, the sum of b + c is about 10 to 30, the sum of a ~ b ~ c being 100. In the above formula, - up to about 80 percent of M may be replaced by one or more of any transition metal other than iron, cobalt and nic~el. Suitable replacements include silicon, chromium, vanadium, aluminum, tin, antimony, germanium, indium, beryllium, molybdenum, titanium, manganese, tungsten, zirconium, hafnium and copper, for example. The phos-phorus content of the alloy will ordinarily be derived 35 from ferrophosphorus, which may be of any suitable phos- :
phorus content, such as commercially available grades con-taining about 18 and 25 percent by weight phosphorus.
The boron trioxide flux comprises compositions z~ ~ ~
of the formula B2O3 of about 95 weight percent purity, preferably better than about 98 weight percent purity, the balance being represented by incidental impuritiess or intentional additives which are substantially inert, that is to say, that they do not materially interfere with the intended function of the boron trioxide flux.
Suitable boron trioxide fluxes have a melting point between about 400C and 600C, preferably between about 400 and 500C, and have a vapor pressure of below about 20 micron.
In the fluxes of the present invention which additionally contain an oxide of iron, cobalt and/or nickel, the oxide is suitably chosen to correspond to the major metal component of the alloy. For example, if iron is the only or major metal component of the alloy, the oxide component in the flux desirably, but not neces-sarily, is an oxide of iron. Nic~el-containin~ melts desirably are refined under a flux-containing nickel oxide. The flux desirably contains from about 20 to ~0 percent by weight boron trioxide.
In the melting operation the metal oxide (e.g.
iron, cobalt or nic~el oxide) coacts with the boron trioxide to obtain the desired result. I~ is believed that oxygen from the metal oxide combines with titanium metal contained in the melt as an impurity, perhaps forming TiO2, which is then bound in the molten flux.
The boron trioxide seems to act as a coagulant for the titanium dioxide as well as for other particulate matter which may be contained in the melt. Moreover, the boron trioxide, because of its acidic character, seemingly tends to prevent oxidation of phosphorus, if present, to the five valent oxide state, as might occur due to presence of small amounts of oxygen in the melt. In the five va-lent state, phosphorus is volatile under refining condi-tions encountered in ma~ing the alloys here under con-sideration.
Of the oxides of iron, namely FeO, Fe2O3 and Fe3O~, all are suitable, FeO being preferred. Likewise, -' : ~ : - ~
,~ - . - : , , 7Z~
any of the oxicles of cobalt, CoO, Co2O3, as well as Co3O~, may be employed. However, for reasons of high cost, use of oxides of cobalt is not ordinarily preferred.
Nickel oxide, for reasons of availability as well as efectiveness, is the preferred metal oxide. Metal oxides of commercial degree of purity are suitable for use.
The boron trioxide (B2O3) similarly may be of any degree commercial purity.
In the metal oxide containing fluxes, the boron trioxide is desirably employed in amount of 20 to 80 per-cent by weight, preferably 30 to 70 percent by weight, most preferably 40 to 60 percent by weight of the flux, the balance being represented by the metal oxide. Of course, if desired, other components which do not mate-rially interfere with the protective and refining func-tions of the flux may be included in the flux composition for any desired purpose, e.g. melting point reduction, although addition of other components is not ordinarily preferred.
The flux compositions are employed in amount sufficient to provide a flux layer of between about 1 and 50 millimeter thickness, preferably between about 2 and 10 millimeter thic~ness on top of the molten metal alloy.
It is an advantage of these flux compositions that their solubility in the alloys is generally low, so that grosscontamination of the alloy with the flux is avoided.
Furthermore, minor contamination of the alloy with boron values from the flux is generally not deleterious, that is to say that such contamination would not adversely affect the glass-forming capabilities of the alloy, nor its properties in the solid state.
The temperature of the alloy melt can be bet-ween about 1000C and 1500C, and preferably between about 1100C and 1~00C~ The temperature of the boron trioxide flux can be between about 900C and 1400C.
To prevent oxidation and loss of phosphorus value from the alloy, the boron trioxide flux should be present at tempelatures leading normally to oxidation , .;:~ : . , : : .
, ~ ~, . ': -``' ;37;~
and/or evaporation of phosphorus values, and in particular the boron trioxide should be present when the alloy is in the molten state. The boron trioxide, to obtain the full benefit of its function, is desirably added to the cold charge. If it is added after the alloy is melted, con-siderable amounts of phosphorus can be lost.
To fulfill its refininy function, the flux should remain in contact with the surface of the melt at melting temperature for a tim~ period for at least about one minute, desirably of at least about 5 minutes. Con-tact times of, say, between about 5 min~tes and 5 hours, desirably of between about 30 minutes and about 3 hours are eminently suitable. If desired, the melt may be agitated. Suitable melting furnaces include those lined with high temperature ceramic materials. Preferred fur-nace linings are ma~e from magnesia, zirconia and alumina.
If desired, suitable inert atmospheres may be provided above the flux, including such as those provided by helium or argon. Alternatively, the melting operation may be conducted under vacuum~ However, provision of inert atmospheres is not essential. If an inert atmosphere is supplied, argon is preferred.
Iron, nickel, phosphorus, and boron containiny glass-~orming alloy compositions were prepared by melting together under vacuum raw materials of the following purity: iron, 99.9 weight percent pure; nickel, 99.9 weight percent pure; nickel boride, 99 weight percent pure having boron content of between about 17 and 19 weight percent; ferrophosphorus (Type I) containin~ 61.43 weight percent iron and 20.39 weight percent boron; ferro-phosphorus (Type II) containing 79 weight percent iron and 21 weiyht percent phosphorus. To each charge there was added an amount of Fe40Ni40Pl4 6 ( metal alloy to provide an initial susceptor for induction heatiny of the charge. No Fe40Ni~OP14B6 was of sample 5 since the ferrophosphorus employed coupled suEficiently with the racliation. The charye was contained .
..
. T~
.
72~3 in a m~gnesia crucible covc-red with boron trioxide and heated by means oE induction heatiny coils. The melt of Examples 1, 2, 4, 5 was maintained under vacuum under a layer of B2O3 flux at a temperature of 1200C for one hour, before casting it into ingots. The melt o~ Example 3 was soaked at 1300~C for 1 hour. The amounts of materials charged are summarized in Table 1 below:
Table 1 Char~e (~rams) Ferro-Example phosphorus Fe Ni P B alloy Fe Ni NiB B2O3 - 40 - 40-14~
1915 (I)~00 263 895 193 136 21200 (I) 1030 3823 (I)707 35~ 895 199 154 44937 (I)2265 2151 5370 llG0 300 5381~ (II) ~98 3654 773 The cast ingots were subjected to analysis for insolubles, oxygen, silicon, calcium, iron, nickel, phos-phorus, and boron. The ingot obtained in Example 3 was further subjected to a second melt cycle at 1200C for 1 hour in vacuum under a flux of B2O3. The remelted alloy was again cast into an ingot and subjected to analysis.
The results of the analysis are shown in Table ~I below.
Iron, nickel, boron and phosphorus were deter-mined by wet chemistry; oxygen was determined by placing pieces of raw alloy in a graphite boat in a Leco oxygen analyzer. This method determines only dissolved oxygen, but not chemically bonded oxygen. The procedure for determining insolubles involved dissolving a 2 ~ram sample of the solid ingot in 100 milliliter of a reagent solu-tion composed of 50 milliliter nitric acid (70~ H~03);
10 milliliter of sulfuric acid (100~ H2SO4) and ~0 milli-liter of water. The alloy was refluxed in the reagent solution until disso ved. The resultant solution was filtered thro~gh an analytical filter to determine in-soluble content as ash residue. Silicon and calcium were determined by takiny an aliquot part of the solution, evaporating the solution, mixing the residue with spec-..~
:
, - , ~ , : ., trographic grade graphite and determining the traces by emissions spectroscopy.
Table 2 Analytica] Results Weight Percent Insoluble S~MPLE Test Oxy~en Si Ca Fe Ni P B
1 1.29 0.031 0.05 less 40014 49.51 9.82 0.79 than 0.03 3 0.65 0.14 0.03 less 41.99 47.64 9.19 1.1 than 0.01 4 1.1 0.17 0.51 less 41.52 47.87 9.11 0.~9 than 0.05 0.03 0.01 0.03 less 44.21 45.52 8.93 1.35 than 0.03 This example illustrates production of an alloy containing Fe: 45.9 -~ 1 percent by weight; Ni: 44.6 + 1 percent by weight; P: 7.85 + 0.32 percent by weight;
- B: 1.45 + 0.11 percent by weight. The raw materials charged are iron, electrolytic fragments~ 99.9 percent pure; nickel pellets, 99.9 percent pure; ferrophosphorus, low silicon grade (less than about 0.5 percent silicon~; -nickel~boron, low aluminum grade tas available, for example, from Shieldalloy Company). Prior to and during the charging operation the furnace is purged with argon gas. The required amounts of ironl nickel and ferrophos-phorus are charged to the furnace, and the charge is gradually heated until melting. At that point, an oxi-dizing acid flux consisting of about 50 weight percent nickel oxide and about 50 weight percent B2O3 is added to the molten charge in an amount of about 8 lbs. per
GL~SS-FO~I~NG ~LOY MEL1'S
. . ~
BACKGROU~D OF TH~ INVENTION
... .
Recent advances in the metallurgical ar.s in-clude development of alloys which, ~ihen rapidly quench-ed from the melt at rates in excess of about 104 to 106C
per second, form glassy ~amorphous) solids. Such glass-forming alloys commonly are based on transition metals, usually iron, nickel and/or cobalt, in conjunction with one or more metalloids of phosphorus, boron and carbon.
- Glass-forming alloys are, for examplel described in U.S.
Pat. 3,856,513 issued December 24, 1974 to Chen et al.
Preparation of phosphide based melts of glass-formin~ alloys under ambient atmosphere leads to oxide inclusions in the glassy metal product. The conventional method of excluding the ambient atmosphere by vacuum melting leads to possible losses of phosphorus values from the melt due to evaporation-. Iron phosphide is a basic ingredient in many glass-forming metallic alloy compositions, and in the high purity form required for such purpose, it is quite costly. Inexpensive forms of iron phosphide available are impure and contain phosphorus in form which can evaporate upon heatin~, and which tends to form volatile phosphorus pentoxide, and which poses a safety hazard and results in changes of the alloy compo-sition. Glassy solid structures are obtained from such alloys by processes such as the melt spin process wherein a fine jet o~ the molten alloy is impinc3ed upon a rapidly movinc~ chill surface for solidification. Orifice dia-meters in this process are exceedingly s~nall, and orifice "
,~.
;fz~3 .
pluggage on account of solid impurities contained in the melt can represent seri~us problems. Iron, cobalt or niekel based phosphorus-containing glass-forming alloys whieh additionally contain boron as a metalloid are particularly prone to contamination with solid partieles.
In such alloy, these particles were found to be pre-dominantly small partieles of TiO2 and/or TiBo3, both of whieh have high melt points, and both of whieh are rela-tively insoluble in the melt. It was ~ound that titanium is an impurity commonly contained in ferrophosphorus, which is used as a source of phosphorus in making these alloys, although titanium may also be present as contami-nant in other raw materials employed in making these alloys.
The present invention provides refining flux for redueing oxidation of and loss of phosphorus values from phosphorus-containing alloys, espeeially phosphorus-eon-taining iron, niekel and~or cobalt-based alloys.
- SVMM~RY OF THE INVENTIO~
Phosphorus-containing metallic glass-forming alloy melts are covered with a layer o~ molten boron tri-oxide flux. Such layer protects the melt from oxidation, dissolves oxide partieulates and impurities from the molten metal alloy and prevents the evaporation of p~os-phorus values. The flux floating on the alloy melt will not interfere with subsequent easting or spinning opera-tions, and the alloy melt can be replenished direetly through the flux layer. Alloys prepared according to the process of the present invention leave minimum residues in the jetting crucible in subsequent melt spin operations~
Phosphorus-containing iron, nickel and/or cobalt-based alloys are desirably melted under a boron trioxide flux additionally comprising oxides o iron, niekel and/or eobalt. The ~lux layer protects the molten alloy from oxidationt reduces or eliminates contamination of the melt with particulate matter, especially metal oxides, and pre-vents loss of phospllorus values by vaporization.
'' ` ! ' -'; ;~ ~
DETAILED ~ESCRIPTION OF THE INVENTION
.
Metallic glass-formin~ alloys which benefit from protection by boron trioxide flux contain phosphorus as a metalloid component, alone or together with other metalloids, such as boron, ca:rbon and silicon. The phosphorus component of such alloys is usually contributed by ingredients having the formulas FePx, NiPX, CoPx, MnPx, wherein x is between abut 0.3 and 1.1 and preferably bet-ween about 0.5 and 1. Preferred alloy compositions include alloys utilizing as source of phosphorus FePx wherein x is between about 0.5 and 1. Pre:Eerred allo.y compositions in-clude transition metal alloys containing between about 3 - and 25 weight percent phosphorus. These alloys have a phosphorus partial pressure of less than 20 micron, and melting points of between about 900C and 1200C.
Phosphorus-containing alloys based on one or more of iron~ nickel and/or cobalt which benefit from melting under the refining boron trioxide flux which additionally contains oxides of iron, nickel and/or cobalt have the general formula MaPbYC wherein M is a metal se-lected from one or more of the group consisting of iron, cobalt and nickel; P represents phosphorus; Y represents a metalloid selected from one or both of the group con-sisting of boron and carbon; and a, b and c are in atomic percent, wherein a is about 70 to 90, b is 0-20, but desirably at least 1, the sum of b + c is about 10 to 30, the sum of a ~ b ~ c being 100. In the above formula, - up to about 80 percent of M may be replaced by one or more of any transition metal other than iron, cobalt and nic~el. Suitable replacements include silicon, chromium, vanadium, aluminum, tin, antimony, germanium, indium, beryllium, molybdenum, titanium, manganese, tungsten, zirconium, hafnium and copper, for example. The phos-phorus content of the alloy will ordinarily be derived 35 from ferrophosphorus, which may be of any suitable phos- :
phorus content, such as commercially available grades con-taining about 18 and 25 percent by weight phosphorus.
The boron trioxide flux comprises compositions z~ ~ ~
of the formula B2O3 of about 95 weight percent purity, preferably better than about 98 weight percent purity, the balance being represented by incidental impuritiess or intentional additives which are substantially inert, that is to say, that they do not materially interfere with the intended function of the boron trioxide flux.
Suitable boron trioxide fluxes have a melting point between about 400C and 600C, preferably between about 400 and 500C, and have a vapor pressure of below about 20 micron.
In the fluxes of the present invention which additionally contain an oxide of iron, cobalt and/or nickel, the oxide is suitably chosen to correspond to the major metal component of the alloy. For example, if iron is the only or major metal component of the alloy, the oxide component in the flux desirably, but not neces-sarily, is an oxide of iron. Nic~el-containin~ melts desirably are refined under a flux-containing nickel oxide. The flux desirably contains from about 20 to ~0 percent by weight boron trioxide.
In the melting operation the metal oxide (e.g.
iron, cobalt or nic~el oxide) coacts with the boron trioxide to obtain the desired result. I~ is believed that oxygen from the metal oxide combines with titanium metal contained in the melt as an impurity, perhaps forming TiO2, which is then bound in the molten flux.
The boron trioxide seems to act as a coagulant for the titanium dioxide as well as for other particulate matter which may be contained in the melt. Moreover, the boron trioxide, because of its acidic character, seemingly tends to prevent oxidation of phosphorus, if present, to the five valent oxide state, as might occur due to presence of small amounts of oxygen in the melt. In the five va-lent state, phosphorus is volatile under refining condi-tions encountered in ma~ing the alloys here under con-sideration.
Of the oxides of iron, namely FeO, Fe2O3 and Fe3O~, all are suitable, FeO being preferred. Likewise, -' : ~ : - ~
,~ - . - : , , 7Z~
any of the oxicles of cobalt, CoO, Co2O3, as well as Co3O~, may be employed. However, for reasons of high cost, use of oxides of cobalt is not ordinarily preferred.
Nickel oxide, for reasons of availability as well as efectiveness, is the preferred metal oxide. Metal oxides of commercial degree of purity are suitable for use.
The boron trioxide (B2O3) similarly may be of any degree commercial purity.
In the metal oxide containing fluxes, the boron trioxide is desirably employed in amount of 20 to 80 per-cent by weight, preferably 30 to 70 percent by weight, most preferably 40 to 60 percent by weight of the flux, the balance being represented by the metal oxide. Of course, if desired, other components which do not mate-rially interfere with the protective and refining func-tions of the flux may be included in the flux composition for any desired purpose, e.g. melting point reduction, although addition of other components is not ordinarily preferred.
The flux compositions are employed in amount sufficient to provide a flux layer of between about 1 and 50 millimeter thickness, preferably between about 2 and 10 millimeter thic~ness on top of the molten metal alloy.
It is an advantage of these flux compositions that their solubility in the alloys is generally low, so that grosscontamination of the alloy with the flux is avoided.
Furthermore, minor contamination of the alloy with boron values from the flux is generally not deleterious, that is to say that such contamination would not adversely affect the glass-forming capabilities of the alloy, nor its properties in the solid state.
The temperature of the alloy melt can be bet-ween about 1000C and 1500C, and preferably between about 1100C and 1~00C~ The temperature of the boron trioxide flux can be between about 900C and 1400C.
To prevent oxidation and loss of phosphorus value from the alloy, the boron trioxide flux should be present at tempelatures leading normally to oxidation , .;:~ : . , : : .
, ~ ~, . ': -``' ;37;~
and/or evaporation of phosphorus values, and in particular the boron trioxide should be present when the alloy is in the molten state. The boron trioxide, to obtain the full benefit of its function, is desirably added to the cold charge. If it is added after the alloy is melted, con-siderable amounts of phosphorus can be lost.
To fulfill its refininy function, the flux should remain in contact with the surface of the melt at melting temperature for a tim~ period for at least about one minute, desirably of at least about 5 minutes. Con-tact times of, say, between about 5 min~tes and 5 hours, desirably of between about 30 minutes and about 3 hours are eminently suitable. If desired, the melt may be agitated. Suitable melting furnaces include those lined with high temperature ceramic materials. Preferred fur-nace linings are ma~e from magnesia, zirconia and alumina.
If desired, suitable inert atmospheres may be provided above the flux, including such as those provided by helium or argon. Alternatively, the melting operation may be conducted under vacuum~ However, provision of inert atmospheres is not essential. If an inert atmosphere is supplied, argon is preferred.
Iron, nickel, phosphorus, and boron containiny glass-~orming alloy compositions were prepared by melting together under vacuum raw materials of the following purity: iron, 99.9 weight percent pure; nickel, 99.9 weight percent pure; nickel boride, 99 weight percent pure having boron content of between about 17 and 19 weight percent; ferrophosphorus (Type I) containin~ 61.43 weight percent iron and 20.39 weight percent boron; ferro-phosphorus (Type II) containing 79 weight percent iron and 21 weiyht percent phosphorus. To each charge there was added an amount of Fe40Ni40Pl4 6 ( metal alloy to provide an initial susceptor for induction heatiny of the charge. No Fe40Ni~OP14B6 was of sample 5 since the ferrophosphorus employed coupled suEficiently with the racliation. The charye was contained .
..
. T~
.
72~3 in a m~gnesia crucible covc-red with boron trioxide and heated by means oE induction heatiny coils. The melt of Examples 1, 2, 4, 5 was maintained under vacuum under a layer of B2O3 flux at a temperature of 1200C for one hour, before casting it into ingots. The melt o~ Example 3 was soaked at 1300~C for 1 hour. The amounts of materials charged are summarized in Table 1 below:
Table 1 Char~e (~rams) Ferro-Example phosphorus Fe Ni P B alloy Fe Ni NiB B2O3 - 40 - 40-14~
1915 (I)~00 263 895 193 136 21200 (I) 1030 3823 (I)707 35~ 895 199 154 44937 (I)2265 2151 5370 llG0 300 5381~ (II) ~98 3654 773 The cast ingots were subjected to analysis for insolubles, oxygen, silicon, calcium, iron, nickel, phos-phorus, and boron. The ingot obtained in Example 3 was further subjected to a second melt cycle at 1200C for 1 hour in vacuum under a flux of B2O3. The remelted alloy was again cast into an ingot and subjected to analysis.
The results of the analysis are shown in Table ~I below.
Iron, nickel, boron and phosphorus were deter-mined by wet chemistry; oxygen was determined by placing pieces of raw alloy in a graphite boat in a Leco oxygen analyzer. This method determines only dissolved oxygen, but not chemically bonded oxygen. The procedure for determining insolubles involved dissolving a 2 ~ram sample of the solid ingot in 100 milliliter of a reagent solu-tion composed of 50 milliliter nitric acid (70~ H~03);
10 milliliter of sulfuric acid (100~ H2SO4) and ~0 milli-liter of water. The alloy was refluxed in the reagent solution until disso ved. The resultant solution was filtered thro~gh an analytical filter to determine in-soluble content as ash residue. Silicon and calcium were determined by takiny an aliquot part of the solution, evaporating the solution, mixing the residue with spec-..~
:
, - , ~ , : ., trographic grade graphite and determining the traces by emissions spectroscopy.
Table 2 Analytica] Results Weight Percent Insoluble S~MPLE Test Oxy~en Si Ca Fe Ni P B
1 1.29 0.031 0.05 less 40014 49.51 9.82 0.79 than 0.03 3 0.65 0.14 0.03 less 41.99 47.64 9.19 1.1 than 0.01 4 1.1 0.17 0.51 less 41.52 47.87 9.11 0.~9 than 0.05 0.03 0.01 0.03 less 44.21 45.52 8.93 1.35 than 0.03 This example illustrates production of an alloy containing Fe: 45.9 -~ 1 percent by weight; Ni: 44.6 + 1 percent by weight; P: 7.85 + 0.32 percent by weight;
- B: 1.45 + 0.11 percent by weight. The raw materials charged are iron, electrolytic fragments~ 99.9 percent pure; nickel pellets, 99.9 percent pure; ferrophosphorus, low silicon grade (less than about 0.5 percent silicon~; -nickel~boron, low aluminum grade tas available, for example, from Shieldalloy Company). Prior to and during the charging operation the furnace is purged with argon gas. The required amounts of ironl nickel and ferrophos-phorus are charged to the furnace, and the charge is gradually heated until melting. At that point, an oxi-dizing acid flux consisting of about 50 weight percent nickel oxide and about 50 weight percent B2O3 is added to the molten charge in an amount of about 8 lbs. per
2,500 lb. metal charge to produce about a 1/8 inch thick layer of flux. The melt is refined under this flux at a temperature of about 1,180 to l,200C for 20 to 30 minutes r takin~ care to avoid temperatures in excess of 1200C during the refining operation. Thereafter, the flux is skin~ed and the nickel boron is added to the melt.
The heat is finished under an argon blanket. Total :``' ' -, v~
_9_ refining and holding time at the 1,180 to l,200C isabout 45 to 60 minutes. The refined alloy is then cast at about l,000C.
Using identical raw materials, alloy of the above composition prepared using the NiO/B2O3 flux as above described had a titanium content of only 0.04 per-cent by weight, whereas an alloy obtained under other-wise identical conditions from the same raw materials, but without use of the flux, had a titanium content about 0.16 percent by weigh~. Furthermore, alloy prepared under conditions of the present invention had significantly lower contamination with other oxidizable elements which tend to form insoluble solid oxides. As a consequence, metal refined in accordance with the present invention r as above described, caused substantially less restric-tion of a casting nozzle in a subsequent spin casting operation.
The heat is finished under an argon blanket. Total :``' ' -, v~
_9_ refining and holding time at the 1,180 to l,200C isabout 45 to 60 minutes. The refined alloy is then cast at about l,000C.
Using identical raw materials, alloy of the above composition prepared using the NiO/B2O3 flux as above described had a titanium content of only 0.04 per-cent by weight, whereas an alloy obtained under other-wise identical conditions from the same raw materials, but without use of the flux, had a titanium content about 0.16 percent by weigh~. Furthermore, alloy prepared under conditions of the present invention had significantly lower contamination with other oxidizable elements which tend to form insoluble solid oxides. As a consequence, metal refined in accordance with the present invention r as above described, caused substantially less restric-tion of a casting nozzle in a subsequent spin casting operation.
Claims (10)
1. A process of melting phosphorus-containing glass-forming transition metal alloys characterised in that the exposed surface of said metal alloy is covered with a layer of a molten flux composition comprising boron trioxide.
2. The process of claim 1 wherein said alloy has a phosphorus content of between about 3 weight percent and about 25 weight percent.
3. The process of claim 1 wherein said flux in contact with the melt is at a temperature within the range of about 900°C to 1400°C.
4. The process of claim 1 wherein the flux composition is employed in amount sufficient to provide a flux layer of between about 2 and 50mm thickness.
5. The process of claim 1 where in the alloy has the formula MaPbYc wherein M is a metal selected from the group consisting of iron, cobalt, nickel, and mixtures thereof in any proportion;
P represents phosphorus;
Y is a metalloid selected from the group con-sisting of boron, carbon, and mixtures thereof in any proportion; a, b and c are in atomic percent; and a is about 70 to 90, b is 0 to 20 the sum of b + c is about 10 to 30, the sum of a + b + c being 100, and wherein the flux comprises oxides of iron, nickel, and/or copper together with boron trioxide.
P represents phosphorus;
Y is a metalloid selected from the group con-sisting of boron, carbon, and mixtures thereof in any proportion; a, b and c are in atomic percent; and a is about 70 to 90, b is 0 to 20 the sum of b + c is about 10 to 30, the sum of a + b + c being 100, and wherein the flux comprises oxides of iron, nickel, and/or copper together with boron trioxide.
6. The process of claim 5 wherein the flux comprises between about 20 and 80 percent by weight of B2O3, and between about 80 and 20 percent by weight of one or more oxides of iron, cobalt and nickel.
7. The process of claim 5 wherein the alloy is an alloy of iron and nickel.
8. The process of claim 7 wherein the alloy contains both phosphorus and boron, in combination.
9. The process of claim 8 wherein the flux comprises between about 20 and 80 weight percent of B2O3, and correspondingly between about 80 and 20 weight percent of NiO.
10. The process of claim 5 wherein the alloy comprises about 46 + 1 percent by weight of Fe; about 45 + 1 percent by weight of Ni; about 8 + 0.5 percent by weight of P; about 1 + 0.5 percent by weight of B, where-in the phosphorus is derived from ferrophosphorus, where-in the flux comprises about equal amounts of NiO and B2O3, and the molten alloy is held in contact with the flux for a period of between about 5 minutes and 5 hours.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US925,579 | 1978-07-17 | ||
| US925,578 | 1978-07-17 | ||
| US05/925,579 US4175950A (en) | 1978-07-17 | 1978-07-17 | Preparation of phosphorus containing metallic glass forming alloy melts |
| US05/925,578 US4181521A (en) | 1978-07-17 | 1978-07-17 | Preparation of glass-forming alloys under a refining metal oxide/boron trioxide slag |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1120728A true CA1120728A (en) | 1982-03-30 |
Family
ID=27129912
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000331545A Expired CA1120728A (en) | 1978-07-17 | 1979-07-10 | Preparation of phosphorus-containing metallic glass-forming alloy melts |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0007062B1 (en) |
| CA (1) | CA1120728A (en) |
| DE (1) | DE2961066D1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4375371A (en) * | 1981-06-12 | 1983-03-01 | Allegheny Ludlum Steel Corporation | Method for induction melting |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE245197C (en) * | ||||
| DE649284C (en) * | 1932-05-15 | 1937-09-23 | Electrochimie D Electrometallu | Slag for the production of low-oxygen steel |
| DE639131C (en) * | 1934-07-02 | 1936-11-28 | Electrochimie D Electrometallu | Process for the production of alloys containing boron |
| DE678763C (en) * | 1935-02-26 | 1939-07-20 | Heraeus Vacuumschmelze Akt Ges | Process for accelerating metallurgical slag reactions |
| DE2246723B1 (en) * | 1972-09-22 | 1973-09-06 | Ver Deutsche Metallwerke Ag | Non ferrous melt surface protection - using a glass compsn |
| US3856513A (en) * | 1972-12-26 | 1974-12-24 | Allied Chem | Novel amorphous metals and amorphous metal articles |
-
1979
- 1979-07-04 DE DE7979102260T patent/DE2961066D1/en not_active Expired
- 1979-07-04 EP EP19790102260 patent/EP0007062B1/en not_active Expired
- 1979-07-10 CA CA000331545A patent/CA1120728A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| EP0007062A1 (en) | 1980-01-23 |
| DE2961066D1 (en) | 1981-12-24 |
| EP0007062B1 (en) | 1981-10-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CH375903A (en) | Niobium alloy | |
| EP0574514A4 (en) | Master alloy hardeners | |
| CN109295330B (en) | Method for refining nitride inclusions in nickel-based wrought superalloy | |
| CN110408806A (en) | A kind of Al-Nb-Ta intermediate alloy and preparation method thereof | |
| US4175950A (en) | Preparation of phosphorus containing metallic glass forming alloy melts | |
| JPH0364574B2 (en) | ||
| US3625676A (en) | Vanadium-aluminum-titanium master alloys | |
| CN110408816A (en) | A kind of nickel boron carbon intermediate alloy and preparation method thereof | |
| US4812290A (en) | Third element additions to aluminum-titanium master alloys | |
| CA1120728A (en) | Preparation of phosphorus-containing metallic glass-forming alloy melts | |
| CA1065579A (en) | Methods of making reactive metal silicide | |
| US4361442A (en) | Vanadium addition agent for iron-base alloys | |
| CA1190416A (en) | Method of alloying calcium and aluminum into lead | |
| US4181521A (en) | Preparation of glass-forming alloys under a refining metal oxide/boron trioxide slag | |
| US4375371A (en) | Method for induction melting | |
| US4229214A (en) | Process for combined production of ferrosilicozirconium and zirconium corundum | |
| CN110358957A (en) | A kind of nickel vanadium intermediate alloy and preparation method thereof | |
| US3685985A (en) | Method for the removal of impurities from metallic zinc | |
| US4526613A (en) | Production of alloy steels using chemically prepared V2 O3 as a vanadium additive | |
| CN110541085B (en) | Preparation method of aluminum cupronickel alloy | |
| Thomas | The Chemistry, Purification and Metallurgy of Plutonium | |
| EP0159459B1 (en) | Production of tool steels using chemically prepared v2o3 as a vanadium additive | |
| JPS5843456B2 (en) | Rare earth↓-silicon alloy manufacturing method | |
| JPH04120225A (en) | Manufacture of ti-al series alloy | |
| SU885310A1 (en) | Method of processing silumine slags |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |