US3592637A

US3592637A - Method for adding metal to molten metal baths

Info

Publication number: US3592637A
Application number: US708267A
Authority: US
Inventors: Charles M Brown; Nicholas J Pappas; Harry J Brown
Original assignee: Union Carbide Corp
Current assignee: Elkem Metals Co LP
Priority date: 1968-02-26
Filing date: 1968-02-26
Publication date: 1971-07-13
Anticipated expiration: 1988-07-13
Also published as: ES364055A1; PL88899B1; CS199224B2; DE1909579B2; DE1909579A1; DE1909579C3; BE728694A; JPS4841405B1; SE367437B; FR2002638A1; SU456415A3; NO129408B; GB1264547A

Abstract

A METHOD OF ADDITION OF A METAL TO A MOLTEN METAL BATH BY MIXING THE ALUMINUM TO BE DISSOLVED IN FINELY DIVIDED FORM WITH A SOLUTION PROMOTING ALUMINUM, ALSO IN FINELY DIVIDED FORM, AND ADDING THE MIXTURE TO MOLTEN METAL.

Description

July 13, 1971 C. M. BROWN ETAL Filed Feb E 50% Mn 50% {\l L Compact At 760 C m Mn Undissolved Kh-gblgzM 40/ AI All v 0 r1 oy ai 760 C 01 v l 0 5 l0 I5 Time, Minmes Afler Addition INVENTORS TTORNEY United States Patent 3,592,637 METHOD FOR ADDING METAL T0 MOLTEN METAL BATHS Charles M. Brown, Lewiston, Nicholas J. Pappas, Snyder, and Harry J. Brown, Lewiston, N.Y., assignors to Union Carbide Corporation Filed Feb. 26, 1968, Ser. No. 708,267 Int. Cl. C22c 1/02 US. Cl. 75-138 11 Claims ABSTRACT OF THE DISCLOSURE A method of addition of a metal to a molten metal bath by mixing the aluminum to be dissolved in finely divided form with a solution promoting aluminum, also in finely divided form, and adding the mixture to molten metal.

This invention relates to the addition of metallic materials to molten metal baths. More particularly, the present invention relates to addition agents formed of finely divided solid metal particles having improved solution rates in molten metal baths.

It is a common practice in metallurgical operations to provide an ultimate desired alloy composition by the introduction of solid metal additives to molten metal baths of a base metal. For example, manganese is added to molten aluminum in the form of manganese-aluminum alloy containing about 5-20% manganese, to provide increased strength in wrought aluminum products. Also, chromium, tungsten, molybdenum, vanadium, iron, cobalt, copper, nickel, columbium and other metals are commonly added in pre-alloyed form to molten metal baths to obtain a particular alloy product. Chromium, for example, has been added to aluminum baths to provide improved corrosion resistance and molybdenum, iron, vanadium and chromium have been added to titanium as stabilizers.

The past practices however have almost universally employed relatively expensive pre-alloyed additions which did not have completely satisfactory solution rates and quite often result in large and highly undesirable temperature drops in the bath to which they are added.

It is therefore an object of the present invention to provide metal bearing addition agents which can be economically prepared and which can be effectively and advantageously added directly to molten metal baths.

Other objects will be apparent from the following description and claims taken in conjunction with the drawing which shows a graph illustrating exemplary solution rates for various addition agents, including particular additions in accordance with the present invention.

An addition agent in accordance with the present invention comprises a blended mixture of at least two different finely divided metal bearing materials in particular proportions whereby upon addition to a molten metal bath the metals rapidly dissolve with relatively little temperature drop being developed in the molten metal bath.

The addition agent of the present invention can be considered as comprising a solution promoter material and a principal material; the principal material being generally the metal, whose rapid solution is particularly desired.

In the present invention, the promoter materials include the following elements:

Al Si and the principal materials include the following elements:

Mn V C-b Cr Fe Ta W Co Zr Mo Cu Hf Ti Ni Ag It has been found, as part of the present invention, that a principal material, when blended in finely divided form with a promoter material, in proportions as hereinafter described, can be dissolved in a metal bath at a remarkably increased rate due to coaction between the principal and promoter elements. Thus for example, a mixture of finely divided aluminum with finely divided manganese, in appropriate proportions, results in increased rate of manganese solution upon addition to a molten bath as compared to a =Mn-Al alloy of the same proportions. Similarly, the principal material chromium can be blended with the promoter aluminum to provide increased rate of solution for chromium. That is to say, the solution of any principal material, when blended in finely divided form with any promoter, in accordance with the present invention, will be significantly improved.

In addition to the elemental metals listed above the promoter material can be in the form of an alloy containing at least 50% by weight in the aggregate of promoter elements and in which the aggregate of the principal elements does not exceed a certain value as hereinafter defined.

Correspondingly, the principal material can be an alloy containing at least 50% by weight principal elements and in which the aggregate of alloyed promoter elements is not more than a specified amount also as hereinafter defined.

An important aspect of the present invention as regards solution rate and bath temperature drop is that the relationships of uncombined (i.e. unalloyed) principal material to uncombined promoter material must be within certain limits. These relationships, designated (A), (B) and (C) hereinbelow, are expressed as follows:

Broad:

Percent Effective Principal Material K Percent Effective Promoter MaterialXK Preferred 2 33 Percent Effective Principal MaterialXK, *Percent Effective Promoter MaterialXK where K =The aggregate amount by weight of principal material in the addition agent.

0 K =The aggregate amount by weight of promoter material in the addition agent.

PERCENT EFFECTIVE PRINCIPAL MATERIAL=Z IN THE PRINCIPAL MATERIAL OF-- Wt. of Mn Percent of alloyed Al in the principal Percent Mn= material plus 2X the percent of alloyed Total wt. of priu- Si in the principal material.

cipal elements Wt. of Ti 1.25X the percent of alloyed Al in the Plus percent Ti= principal material plus 3X the percent of Total wt. of principal alloyed Si in the principal material.

elements Wt. of V 0.66X percent of alloyed Al in the principal Plus percent V= X material plus 3X the percent of alloyed Total wt. of principal Si in the principal material.

elements Wt. of Mo 1.25X percent of alloyed Al in the principal Plus percent Mo= X material plus 2X the percent of alloyed Total wt. of principal Si in the principal material.

elements Wt. of W 1.25X percent of alloyed Al in the principal Plus percent W= material plus 10X the percent of alloyed Total Wt. of principal Si in the principal material.

elements Wt. of 00 2X percent of alloyed Al in the principal Plus percent Co= material plus 2 X the percent of alloyed Total wt. of principal Si in the principal material.

elements Wt. of Fe 0.66 X percent of alloyed Al in the principal Plus percent Fe= X material plus 2X the percent of alloyed Total wt. of principal Si in the principal material.

elements Wt. of Cr 2X percent of alloyed Al in the principal Plus percent Cr= material plus 2X the percent of alloyed Total wt. of principal Si in the principal material.

elements Wt. of Ni 2X percent of alloyed Al in the principal Plus percent Ni= X material plus 2X the percent of alloyed Total wt. of Si in the principal material. principal elements Wt. of Zr 2X percent of alloyed Al in the principal Plus percent Zr= X material plus 3X the percent of alloyed Total wt. of Si in the principal material. principal elements Wt. of Cu 4X percent 01' alloyed Al in the principal Plus percent Cu= X material plus 15X the percent of alloyed Total wt. of Si in the principal material. principal elements Wt. of Hi 4X percent of alloyed Al in the principal Plus percent Hf= X material plus 3X the percent of alloyed Total wt. of Si in the principal material. principal elements Wt of Ag 11X percent of alloyed Al in the principal Plus percent Ag= X material plus 2X the percent of alloyed Total wt. of Si in the principal material. principal elements Wt of Oh 10X percent of alloyed Al in the principal Plus percent Cb: X material plus 5X the percent of alloyed Total wt. of Si in the principal material. principal elements Wt. of Ta 19X percent of alloyed Al in the principal Plus percent Ta= X materiel plus 3X the percent of alloyed Total wt. of Si in the principal material.

principal elements and Where PERCENT EFFECTIVE PROMOTER MATERIAL=E IN THE PROMOTER MATERIAL OF- wt. of Al Total wt. of promoter elements Percent Al=c Percent of alloyed Mn in the promoter material. Plus O.8 X percent of alloyed Ti in the promoter material.

Plus 0.8X percent of alloyed M0 in the promoter material.

Plus 0.8 percent of alloyed W in the promoter mate 'al r1 Plus 1.5X percent of alloyed V in the promoter material. Plus 0.45X percent of alloyed Coin the promoter in erial. Plus ).4 5 1 percent of alloyed Cr in the promoter 111 err Plus 0.45X percent of alloyed Ni in the promoter maten' Plus 0.4

mate

Plus 0. mate materi Plus 0.0 5X percent of alloyed Ta in the promoter material. Plus 1.5X percent of alloyed Fe in the promoter matcri Plus:

In e

materi ma ri me. n

mate

Plus 0.5X percent of alloyed Mn in the promoter material.

Plus percent of alloyed Ti in the promoter a na Plus 0. 3X percent of alloyed V in the promoter Plus 8.5%} percent of alloyed M in the promoter Plus 81x1 percent of alloyed W in the promoter Plus 0.5 l percent of alloyed Co in the promoter Plus 0.5 percent of alloyed Fe in the promoter Wt of Si materi Percent Si: Plus 0.5 percent of alloyed Cr in the promoter Total wt. of mate promoter elements matmaL material.

material.

materi material material.

The foregoing relationships have been discovered as a result of extensive testing and study of the principal and promoter materials.

The relationship (A) as defined above in general represents the overall balance between free or active principal and promoter materials that is required in an addition agent for effective coaction, while relationships (B) and (C) define the amount of free or active principal and promoter elements required, in the principal and promoter materials respectively, for effective coaction and improved solution properties. Relationship (B) shows that only materials containing more than a defined amount of free, i.e. uncombined, unalloyed principal material are suitable, i.e. active enough to function as principal materials, and relationship (C) provides a corresponding relationship for the promoter materials. The definitions Percent Effective Principal Material and Percent Effective Promoter Material further show that the permissible extent of alloying depends upon the particular principal and promoter elements involved. For example, an alloy of 60% Mn, 40% Al will be suitable as a principal material since the Percent Effective Principal Material in such an alloy is 6040=20. However, an alloy of 60% Mn, 40% Si alloy on account of the different interaction between manganese and silicon would not be a suitable principal material and the Percent Effective Principal Material in such an alloy is 602 40=20 which is not 220. An alloy of about 73.5% Mn, 26.5% Si would however be a suitable principal material. As to promoter materials, an alloy of 60% Al, 40% Mn will be a suitable promoter material since the Percent Effective Promoter Material would be 6040=20. An alloy of 60% Al, 40% V however would not be suitable as a promoter material since the Percent Effective Promoter Material in such a case would be 601.5 40=0. Further with respect to the aforementioned relationships (A), (B) and (C), in the more complex addition agents it must be kept in mind that all materials qualifying as principal materials are lumped together for purposes of computing percentages and factors applicable to the Percent Effective Principal Material, and all materials qualifying as promoter materials are lumped together for purposes of computing percentages and factors applicable to the Percent Effective Promoter Material.

The following Examples A through I are given to further illustrate how the foregoing relationships are calculated for specific addition agents.

In the case Where interalloying of principal and promoter material is not present in the addition agent relationships (B) and (C) can be ignored (both the Percent Effective Principal Material and the Percent Effective Promoter Material=l00); also, relationship (A) in this case 1s:

Broad: 10 to Principal Material and 10 to 90% Promoter Material Preferred: 20 to 80% Principal Material and 20 to 80% Promoter Material EXAMPLE A The addition agent is a mixture of 60 parts by weight of finely divided aluminum and 40 parts by weight of finely divided manganese.

Percent Effective Principal Material (B)=l00 (Mn constitutes 100% of the principal material) Percent Effective Promoter Material (C)=1=00 (Al con- The addition agent is a mixture of 60 parts by weight of 80% Mn-20% Al alloy and 40 parts by weight of finely divided elemental aluminum.

K =6O K =40 Percent Effective Principal 4 Material (B) X20=60 Percent Effective Promoter 100 (Al constitutes 100% Material (C) of the promoter material) thus (A) is 60x60 EXAMPLE 0 The addition agent is a mixture of 50 parts by weight of 80% Al-20% Si alloy and 50 parts by weight of Mn-5% Al alloy.

7 K =50 (parts of the prinicpal material: 95% Mn-% Al allo K =50 (parts of the promoter material: 80% Al-20% Si) Percent Efiective Principal 47.5

Material 95 47.5 5 90 Percent Effective Promoter Material thus (A) is EXAMPLE D The addition agent is a mixture of 30 parts of finely divided elemental Mn, parts of Cr and 50 parts of 80% o Al-20% Mn alloy.

K =50 parts of Mn+20 parts of Cr) K (50 parts of 80% Al-20% Mn alloy) Percent Effective Principal Material (B) Mn+40% C1 100 Percent Effective Promoter Material (C) 80 2060 thus 15 m EXAMPLE E The addition agent is a mixture of 80 parts by weight of finely divided Mn-5% Al alloy and 20 parts by weight of finely divided 70% Al-30% Mn alloy.

The addition agent is a mixture of 40 parts by weight of finely divided manganese, 20 parts by Weight of finely divided 80% V-20% -Al alloy and 40 parts by weight of finely divided aluminum.

K =60 (40 parts of Mn+20 parts of 80% V-20% Al) K =4O (40 parts of aluminum) Percent Effective Principal Material (B) Percent Effective Promoter (all of promoter is Material (C) aluminum) 87.7 60 thus 1S m' EXAMPDE G The addition agent is a mixture of 40 parts by weight of finely divided manganese, 20 parts by weight of finely divided 80% Mn-20% Al alloy and 40 parts by weight of finely divided aluminum.

K =60 (40 parts of Mn+20 parts of 80% Mil-20% Al) K =4O (40 parts of aluminum) Percent Effective Principal 56 6. 86.3 Material (B) 93% 56 7%) Percent Effective Promoter =1 0 Material (0) O se.3 c0 thus (A) is 1.3

EXAMPLE H The addition agent is a mixture of 200 parts of 50% Mn-20% Ti-20% Al-10% Si alloy and 200 parts of elemental aluminum.

Percent Effective Principal l( 9 Material (20+- 10 Percent Effective Promoter 100 Material EXAMPLE I thus (A) is =0.257

The addition agent is a mixture of 50 parts of elemental manganese, 50 parts of 40% Ti-40% Al-20% Si alloy, and 100 parts of elemental aluminum. (Note: The Ti-Al- Si alloy is a promoter material since A1+Si 50%.)

Percent Effective Promoter thus (A) is m= To further illustrate the present invention, the following Tables 1(a) and I(b) list various other specific promoter and principal materials, which are effective in the practice of the present invention.

Table I(a) .-'Specific promoter materials (alloys) 70% Al, 30% V 80% Al, 20% Ti 80% Al, 20% M11 75% Si, 25% Fe 70% Si, 5% Mg, bal Fe 60-65% Si, 1% Al, 6% Zr, 2% Ca, 3% Ba, bal Fe Parts of 'll-Al-Si a1loy+100 parts of Al.

- 9 v TableI(b) .Specific principal materials (alloys) As to the physical form of the addition agent of the present invention, it can be used as an uncompacted confined mixture, for example, the mixture of principal and promoter material can be wrapped in metal foil or enclosed in consumable containers. When used in such form it is introduced beneath the surface of the molten bath by customary plunging or immersion devices and techniques. Most often and preferably however the addition agent of this invention is employed in the form of pressed compacts or pellets which preferably have suflicient density so that they sink of their own weight in the molten metal bath. In either case, the initial sizing of the constituent promoter and principal materials is important and should be substantially all finer than 20 mesh for optimum solubility and preferably substantially all finer than 65 i 0.039 which is referred to herein as the solution rate K. The procedure of this example was followed with other additions to obtain their solution rates and these are listed herein below. Increasing numerical values for K, i.e. more negative values, represent more rapid solution rates.

EXAMPLE 2 The procedure of 'Example 1 was followed using 34 gram pellets (78 inch diameter) formed by pressing blended mixtures of materials selected from those listed in Table II(a) at 20,000 psi. in a hydraulic press. The pellets had the densities indicated in Table II(b) which also shows the solution rates obtained.

Other materials, including a commercial manganese containing addition agent Mn hardener-bal. Al) were also tested following the procedure of 'Example 1 and the results are shown in Table II(b) for purposes of comparison:

TABLE II(b) Rate of solution, K Pellet density Mn re- Percent cover-y, Bath temp., C 760 850 G./cc. theor. percent Form of addition, sample:

,.- P-l (5% Mn+95% Al) 1 -0. 032 2. 41 86 95+ P-2 Mn+80% Al) .50 2. 56 83 95+ P-3 (50% Mn+50% Al) 3. 53 88 95+ P4 (90% Mn+10% Al) 1 4. 26 68 95+ 5 (Lofie, FeMn) 8XD -0. 005 95+ P-6 (50% LOFeFeMn+50% Al) -0. 75 3. 1G 64 95+ 7 (5% Mn hardener 1% lumps) 0. 152 95+ 11 Mn flake 150 mesh 0. 250 95+ 12 LoFe, FeMn lumps 95+ 13 60% M11, Al (alloy) 14 LoSi, LoFe, FeMn -8M+20M. 0. 018 95+ P-15 LoSi, LoFe, FeMn EXAMPLE '1 A bath of molten aluminum (5 lbs.) was stabilized at 850 C. and a 1.5% addition (34 grams) of manganese was added as electrolytic manganese flake (2 /s lumps). At the various time increments listed below samples were taken from the bath and analyzed for manganese:

Actual Percent Mn Time from analysis, undissolved addition, percent Mn (by subminutes dissolved traction) The foregoing data plotted conventionally on semi-log coordinates as shown in the drawing gives a slope of l P reperesents pellet additio; 2 Thiis invention.

As can be seen from the data of Table II(b), the addition agents in accordance with the present invention have very fast solution rates, i.e. more negative values for K. In particular it can be seen that additions P-2, P-3, P-6 and P-l5 of this invention have solution rates several times faster than that of the commercial hardener addition 7 and the fully alloyed 60% Mn-40% Al addition 13. The solution rates for P-3 and the commercial hardener are comparatively illustrated in the drawing.

As shown in Table II(b), addition agents of the present invention containing about 50% Mn+50% Al (P-3 and P-6) have remarkably fast solution rates. Thus addition agents containing substantially equal amounts and percentages of Effective Principal Material and Effective Promoter Material are preferred. It will be noted that the mesh electrolytic manganese addition 11 provides a respectable solution rate. However, manganese in this form is not practical as a commercial addition agent for aluminum since it would not readily penetrate the dross which develops on the top of an aluminum bath, oxida tion losses of manganese would be considerable, and there would be problems of pyrophoricity and dusting.

Additional tests were performed to demonstrate the improved principal material solubility rate obtained through the practice of the present invention as illustrated in the following examples.

EXAMPLE 3 Pellets inch diameter) were made by pressing tungsten powder (7 microns) at 5 ton p.s.i. pressure. Pellets thus prepared were added to a molten aluminum 11 1 bath at 850 C. in an amount sutiicient to provide a 1% tungsten addition. No detectable solution of tungsten was obtained.

EXAMPLE 4 Pellets (Ms inch diameter) were made by pressing 50 parts by weight of tungsten powder (7 microns) with 50 parts by Weight of aluminum powder (100-|-325 mesh) at 5 ton p.s.i. pressure. Pellets (density=3.7 g./cc.) thus prepared were added to a molten aluminum bath at 760 C. in an amount sufficient to provide a 1% tungsten addition. The solution rate, K, obtained was 0.036. More than 95% of the added tungsten was dissolved.

EXAMPLE 5 Pellets A; inch diameter) were made by pressing molybdenum powder (7 microns) at 5 ton p.s.i. pressure. Pellets thus prepared were added to a molten aluminum bath at 850 C. in an amount sufficient to provide a 1% molybdenum addition. No detectable solution of molybdenum was obtained.

EXAMPLE 6 Ferrochromium (70% Cr, 2% Si, bal Fe) powder (150 mesh XD) was wrapped in metal foil and added to a molten aluminum bath at 760 C. in an amount sufiicient to provide a 1 /2 chromium addition. The solution rate, K, obtained was 0.002.

EXAMPLE 8 Pellets ("4; inch diameter) were made by pressing 50 parts by weight of ferrochromium powder (150 mesh XD) with 50 parts by weight of aluminum powder (100+325 mesh) at 5 ton p.s.i. pressure. Pellets (density=3.08 g./cc.) thus prepared were added to a molten aluminum bath at 760 C. in an amount sufficient to provide a 1 /2 chromium addition). The solution rate, K, obtained was 0.093. More than 95% of the added chromium was dissolved.

EXAMPLE 9 Elemental chromium powder (150 XD) was wrapped in metal foil and added to a molten aluminum bath at 790 C. in an amount sutficient to provide a 3 /2% chromium addition. The solution rate, K, obtained was 0.068.

EXAMPLE 10 Pellets inch diameter) were made by pressing 50 parts by weight of elemental chromium powder (65 XD) with 50 parts by weight of aluminum powder at 5 ton p.s.i. pressure. Pellets (density=3.15 g./cc.) thus prepared were added to a molten aluminum bath at 760 C. in an amount suflicient to provide a 1 /2% chromium addition. The solution rate, K, obtained was 0.56. More than 95% of the added chromium was dissolved.

EXAMPLE 11 Pellets inch diameter) were made by pressing 50 parts by weight of 85% Mn-9% Si-bal Fe alloy powder (60 XD) with 42 parts by weight of 92% Al-8% Cr powder (65 XD) at 5 ton p.s.i. pressure. Pellets (density=3.21 g./cc.) thus prepared were added to a molten aluminum bath at 760 C. in an amount suflicient to 12 provide a 1 /2% manganese addition. The solution rate, K, obtained was 0.14. More than 95% of the added manganese was dissolved.

EXAMPLE l2 Pellets (73 inch diameter) were made by pressing 37 parts by weight of manganese powder (150 XD) with 63 parts by weight of 60% Al-40% V alloy (65 XD) at 5 ton p.s.i. pressure. Pellets (density=2.65 g./cc.) thus prepared were added to a molten aluminum bath at 760 C. in an amount sufficient to provide a 1 /z% manganese addition. The solution rate, K, obtained was 0.04.

In addition to the foregoing additional tests were conducted to determine the aluminum bath temperature drop for 1.5% Mn additions using a thermocouple immersed in the metal bath for temperature measurements. The results are shown in Table III.

TABLE III Bath temperature drop for 1.5% Mn additions Temp. drop, 0.

Bath temperature, C 730 760 Addition:

(7) Commercial hardener 70 (13-3) 50% Mn+50% Al 8 8 TABLE IV Eficet of compact density on solution rate Solution Percent rate, K,

of max. Density, 760 C. bath Addition agent density g./cc. temp.

(P-3) 50% Mn+50% Al 88 3. 53 0. 55 (P-3) 50% Mn+50% AL 61 2. 4 0. 45 (1 -3) 50% Mn+50% Al. 91 3. 6 0. 42 (P-3) 50% Mn+50% Al 05+ 3.95 0. 027

As can be seen from the foregoing Table IV densities above about 95 of the maximum density are to be avoided since the solution rate drops drastically at such high densities. The preferred densities for the compacted addition agent of the present invention are from about 65 to 90% of the maximum theoretical density.

The effect of initial particle sizing of the constituent materials on the solution rate for the addition agent of the present invention was also investigated using 50% Mn+50% Al compacts (78'', 34 grams) having a density of about 3.50:.05 g./cc. The results are shown in Table V.

TABLE V Solution rate at 760 C., K aluminum size Manganese size 20 mesh 20 x 65 mesh mesh 20 mesh 0. 069 0. 313

0.465 150 mesh 0. 63

Compact siZe (50% Mn+50% Al) Solution rate, K,

minimum dimensioninches: at 760 C. A 0.71

While the foregoing description has particularly described the making of principal material additions to molten aluminum baths, the additions of the present invention can he made to any metal bath in which the principal material is soluble. Such baths include aluminum, titanium, iron, and copper. The mesh sizes referred to herein are United States Sieve Series.

What is claimed is:

1. A process for making metal additions to a molten aluminum bath which comprises introducing into the molten aluminum bath a blended mixture consisting essentially of from about to about 90% of finely divided aluminum and from about 10% to about 90% of at least one finely divided material selected from the group consisting of Mn, Cr, W, Mo, Ti, V, Fe, Co, Cu, Ni, Cb, Ta, Zr, Hf, Ag, and alloys thereof wherein the metal'addition mixture is substantially all dissolved in the molten aluminum bath at an accelerated rate substantially greater than that which would be obtained with alloyed material of the same constituents and with substantially complete retention of the metal addition constituents.

2. A process in accordance with claim 1 whereinthe blended mixture is in the form of compacts having a density of from about 65 to 95 of maximum theoretical density.

3. A process in accordance with claim 1 wherein the blended mixture is in the form of compacts having a density of from about 65 to 95% of maximum theoretical density and wherein the initial particle sizing of the blended mixture is substantially all finer than mesh.

4. A process in accordance with claim 1 wherein the blended mixture is in the form of a compact having a density of from 65% to 95% of maximum theoretical density, wherein the initial particle sizing of the blended mixture is susbtantially all finer than 20 mesh and wherein such compacts have a maximum thickness of not more than about A; inch.

5. A process in accordance with claim 1 wherein the blended mixture contains from about 10% to 90% aluminum and from about 10% to 90% manganese.

6. A process in accordance with claim 1 wherein the blended mixture contains from about 10% to about 90% aluminum and from about 10% to about 90% chromium.

7. A process in accordance with claim 1 wherein the blended mixture contains from about 10% to about 90% aluminum and from about 10% to about 90% ferromanganese.

8. A process in accordance with claim 1 wherein the blended mixture contains from about 10% to about 90% aluminum and from about 10% to about 90% ferrochromium.

9. A process for adding metal additions to a molten aluminum bath which comprises adding to the molten aluminum bath a mixture consisting essentially of from about 10 to about 90% of finely divided aluminum and from about 10 to about 90% of at least one finely divided material selected from the group consisting of manganese, tungsten, molybdenum, chromium, ferrochromium and ferromanganese wherein the metal addition mixture is substantially all dissolved in the molten aluminum bath at an accelerated rate substantially greater than that which would be obtained with alloyed material of the same constituents and with substantially complete retention of the metal addition constituents.

10. A process for making metal additions to a molten aluminum bath which comprises introducing into the molten aluminum bath a blended mixture consisting essentially of from about 10% to about 90% of finely divided aluminum and from about 10 to about 90% of at least one finely divided material selected from the group consisting of Mn, Cr, W, Mo, Ti, V, Fe, Co, Cu, Ni, Cb, Ta, Zr, Hf, Ag, and alloys thereof wherein upon introduction into the molten aluminum bath the aluminum coacts with the selected material and the metal addition mixture is substantially all dissolved in the molten aluminum bath at an accelerated rate substantially greater than that which would be obtained with alloyed material of the same constituents and with substantially complete retention of the metal addition mixture constituents.

11. A process in accordance with claim 1 wherein the blended mixture contains from about 20% to about 80% of finely divided aluminum and from about 20% to about 80% of at least one finely divided material selected from the group consisting of Mn, Cr, W, M0, Ti, V, Fe, Co, Cu, Ni, Cb, Ta, Zr, Hf, Ag, and alloys thereof.

References Cited UNITED STATES PATENTS 2,935,397 5/1960 Saunders et al. 129 3,190,750 6/1965 Staggers et a1. 75138 3,459,540 8/1969 Tisdale et a1 75-129 RICHARD O. DEAN, Primary Examiner U.S. C1. X.R.

Patent No. i 522 637 Dated 13 1 1 2 Inv ntofl Charles M. Brown, Nicholas J. Pappas and Harry J. Brown It is certified that and that said Letters Pate errorappears in the aboveidentified patent at are hereby corrected as shown below:

In column 2 at line 60 delete "Principal" and substitute ---Promoter---.

(SEAL) Attest:

EDWARD M.FLETCHER,JR.

ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents