US2150095A - Method of treating nickel-copper alloys and products resulting therefrom - Google Patents

Description

Patented Mar. 7, 1939 PATENT OFFICE METHOD OF TREATING NICKEL-COPPER ALLOYS AND THEBEFROM PRODUCTS RESULTING Augustus Ernest Kayes, Huntington, W. Va., as-

signor to The International Nickel Company, Inc., New York, N. Y., a corporation of Delaware m. Drawing. Application April 19, 1935, Serial No. 17,258. Renewed August 9, 1938 13 Claims.

The present invention relates to a method of improving nickel and nickel alloys and to the improved product resulting therefrom.

Heretofore it has been customary in the deoxidation of nickel and nickel alloys, particularly nickel-copper alloys, to add a small quantity (about 0.05 to about 0.15%) of magnesium in conjunction with certain preliminary deoxidizers, each as manganese and aluminum. These agents were added for the purpose of counter-acting the harmful effects of sulphur and oxides contained in the metal which rendered the metal nonmalleable and which tended to cause unsound ingots, if not properly taken care of. Although various proposals have been made to overcome the prior disadvantages, none, as far as I am aware, has been wholly satisfactory, practical and acceptable when carried into commercial practice on an industrial scale.

I have discovered that the incorporation of small quantities of zirconium alone or together with phosphorus or boron to the melt of nickel or nickel alloys, especially in conjunction with magnesium and in some cases aluminum, improves the hot malleability of the metal, particularly a nickel-copper alloy and renders'it less red short. In carrying the invention into practice, I have found that zirconium may be introduced through the slag on the surface of the molten metal, or plunged into the metal in the furnace, or may be added in the ladle. 'The quantity of zirconium necessary to accomplish the new results of providing hot malleability and less red shortness varies and depends upon the impurities and substances with which the melt is contaminated. For general purposes, it has been found that about 0.01 to about 0.25%of zirconium alone or together with combinations of .005 to 15% of phosphorus, or 0.003 to 0.02% of boron will give satisfactory results when added to a melt of nickel or nickel alloys, particularly when used in conjunction with about 0.05 to about 0.20% of aluminum and about 0.02 to about 0.15% of magnesium.

For the purpose of giving those skilled in the art a better understanding of the invention, the following illustrative specific examples will be given:

Nickel I have found that improved nickel may be produced by treating a melt of nickel either carbonfree or carbon bearing with zirconium alone or zirconium with phosphorus or boron in conjunction with magnesium. The following schedule indicates the range in percent and the preferred percent of the aforesaid agents to be used in the treatment of nickel.

It is preferred to add the agents to the nickel melt in the following order: zirconium, magnesium, and phosphorus or boron. The additions are made to the melt either in a furnace or in a ladle after tapping from the furnace and before teeming into ingot molds. Satisfactory results have been obtained by having the temperature of the melt at the time of the addition at about 2800" F. to about 3000 F.

The treatment of a melt of nickel with airconium, magnesium, and phosphorus or boron in controlled amounts will eliminate or counteract detrimental effects due .to the presence of impurities, contaminations and deleterious traces encountered in the general refining of nickel and will produce an improved product having no red short range and one which is malleable at all temperatures up to about 2300 F. or about 2500 F. The improved nickel in ingot form can be suitably overhauled, hot and/or cold worked to produce rods, bars, sheets and strip without difficulty and to give a ductile product free from seams.

It is to be noted that the mesence of detrimental elements or constituents in nickel, such as sulfur, selenium, tellurium, refractory particles like silicates and oxides, etc., cause red shortness or a lack of hot malleability at hot forging and rolling temperatures. In prior practice, manganese, aluminum and magnesium were used to counteract the detrimental elements, etc. I have found that the reaction products of aluminum and magnesium including silicates and oxides remained in the melt as non-metallic inclusions and were harmful due to their harmful contribution to red shortness and to the formation of seams. By the utilization of the present treatment, the aforesaid difficulties can be overcome and an improved product can be produced.

Nickel-copper alloys In the treatment of nickel-copper alloys, particularly those containing more than 50% of nickel, "red shortness may be eliminated and a sound and malleable metal may be produced. Thus a nickel-copper alloy having about to nickel and about 23 to 35% of copper as the principal components may be treated in accordance with the principles of the present invention to eliminate, remedy or counteract the effect of detrimental constituents. In carrying the invention into practice, it is preferred to use zirconium in conjunction with phosphorus. These, agents are used in conjunction with aluminum and magnesium in the following percentages:

The aforesaid elements are preferably added in sequence. Thus, aluminum is first added to the melt under treatment, zirconium second, magnesium third and phosphorus last. The addition of these agents may be made either in the furnace or in the ladle. In practice satisfactory results have been obtained by having the temperature of the molten metal at the time of the treatment within a range of about 2700 F. to about 2900 .F.

It has been found that the combination of the aforesaid agents can be varied depending upon the nature and kind of impurities in the molten metal. In some cases, magnesium may be omitted if the melt is substantially free from sulphur.

After the foregoing treatment, the treated nickel-copper alloys can be teemed into ingot molds. The ingots can then be overhauled in accordance with customary practice. After overhauling, the ingot may be submitted to hot and/or cold working to produce rods, bars, sheet, strip, etc., without any difficulty due to red shortness, since the alloy is malleable at all temperatures up to about 2250 F. to about 2350 F. This new result is a distinct improvement over prior procedures which produced nickelcopper alloys which were not commercially malleable for hot working at temperatures below about 1600 to 1700 F.

Nickel-iron-chromium alloys The present invention may be used for the treatment of an alloy containing about 50 to about of nickel, about 0.25% to about chromium alloy has improved malleability over practically the entire high temperature range.

In carrying the invention into practice, a nickel-lron-chromium alloy containing 80% nickel, 6% iron, 14% chromium and less than 0.15% carbon is deoxidized with agents such as aluminum and/or magnesium. After this treatment, about 25% of zirconium and about .01% of boron is added to the melt. The malleableizing elements are thoroughly distributed throughout the melt which is then tapped and teemed. In certain instances, it may be desirable to add a the malleabilizing elements zirconium and boron to the melt in the ladle instead of in the furnace. Satisfactory results have been produced by the present treatment and alloys have been made which are sound and free from blow holes, substantially free from seams or splits or cracks and substantially free from red shortness". The

alloys can now be hot worked without any dimculties due to red shortness" down to a temperature of about 1400 F.

. Nickel-manganese allows It has been found that alloys containing nickel and manganese can be treated by the present invention. Thus, nickelanese alloys containing about 1 to about 20% of manganese can be treated with zirconium, magnesium and phosphorus or zirconium, magnesium and boron to eliminate the effects of detrimental oonstitutents and to produce an improved alloy.

In c ying the invention into practice, a melt of the nickel-manganese alloy may be treated with zirconium first, magnesium second and phosphorus or boron third. The treatment may be made either in the furnace orin the ladle after tapping from the furnace and before teeming into the ingot mold. It has been found that it is preferred to have the temperature of the melt at the time of the addition within the range of 2800 F. to about 3000" 1-. The agents may be used in amounts set forth in the following schedule:

Agent Bangs mm Percent Percent Zirconium 0.01 -0.25 0.06 m1 m 0. 02 -0. l5 0. 0G Phosphorus 0. 01 -0. 06 0. 015' Boron 0. (KB-(L 02 0. (I

The present treatment has resulted in improved products having practically no red short" range and c a commercial malleability at all temperatures up to about 2300 to about 2500 F. It has been found'that nickel manganese alloys in ingot form can be suitably overhauled, hot and/or cold worked to produce rods, bars, sheet and strip without defects. Ductile products substantially free from seams have been obtained.

For the purpose of controlling the addition of a malleableizing element to a melt under treatment and determining the sufllciency of such addition, use is made of the "hammer and anvil" test. In conducting this test, a spoonful (about 3 to 5 lbs.) of melted metal is removed from the furnace and a test bar (about x 1%" x 6" and about 1 lb.) is poured. The solidified test bar is hammered with a sledge hammer (about 10 lbs.). In the event cracks develop, the metal is Judged to be "red short. A further controlled addition of malleableizing element is made to the melt and another test bar is made and tested. This procedure is repeated until the test bar withstands the hand forging operation without cracking. The melt is then treated properly and is poured into the mold.

In industrialpractice, it is to be noted that a series of high temperature bend tests are conducted on material from each melt after the melt has been cast into-ingots and before it is further processed. Thue tests provide a means of measuring the hot ductility and thus predicting the rolling quality of the material. In conducting bend tests, a forged bar 55" thick by 1" wide by 6" long is heated in an electrically controlled furnace to a predetermined temperature. It is then withdrawn from the furnace and bent 180 degrees with a single blow of a steam hammer. If the test piece withstands this deformation without crackingitk asgood; ifnot,itis

called bad. This test is repeated at intervals of 100 F. over the range from 1200' F. to 2300 F.-2500 F. The dimensions of the bend test specimens havebeen so chosen that a good bend at any temperature indicates that the material is capable of being hot worked at that temperature without cracking.

I claim:

1. In the process of treating a mass of conventionally deoxidized and ,malleableized nickel and nickel alloys having red shortness to render the same substantially free from seams and from red shortness that improvement which comprises treating a mass of the aforesaid character while molten and after conventional deoxidizing and malleableizing treatments with a controlled, critical and small amount of zirconium and a member of the group consisting of boron and phosphorus to render said mass, when solidified,

substantially free from seams and from red shortness and to impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleable zone.

2. In the process of treating a mass of conventionally deoxidized and malleableized nickel and nickel alloys having red shortness to render the same substantially free from seams and from red shortness that improvement which comprises treating a mass of the aforesaid character while molten and after conventional deoxidizing and malleableizing treatments with a controlled, critical and small amount within a range of about 0.003% to about 0.75% of zirconium and a member of the group consisting of boron and phosphorus to render said mass, when solidified, substantially free from seams and from red shortness and to impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleable zone.

3. In the process of treating a mass of conventionally deoxidized and malleableized nickel and nickel alloys having red shortness to render the same substantially free from seams and from red shortness that improvement which comprises treating a mass of the aforesaid character while molten and after conventional deoxidizing and malleableizing treatments with a controlled, critical and small amount of zirconium and a member of the group consisting of boron and phosphorus to render said mass, when solidified, substantially free from seams and from red shortness and to impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleable zone, the said zirconium, boron and phosphorus being used within a range of about 0.010% to about 0.25%, about 0.003% to about 0.020%, and about 0.01% to about 0.05%, respectively.

4. The process of treating a mass of malleable nickel and nickel alloys having red shortness to -ender the same substantially free from seams and from red shortness which comprises adding to a mass of the aforesaid character while molten a controlled and restricted amount of zirconium and a member of the group consisting of boron and phosphorus to render said mass, when solidified, substantially free from seams and from red shortness andto impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleable zone, determining the sufiiciency of the controlled and restricted amount of the agent on test samples by the hammer and anvil test while the mass is maintained molten, and continuing the aforesaid operations until the hammer and anv test determines the sufficien- 3 cy of the controlled and restricted amount of the agent added to render the nickel mass, when solidified, substantially free from seams and red shortness and to impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleable zone.

5. The process of treating a mass of malleable nickel and nickel alloys having red shortness to render the same substantially free from seams and from red shortness which comprises treating a mass of the aforesaid character while molten with a controlled and restricted amount of zirconium and a member of the group consisting of boron and phosphorus to render said mass. when solidified, substantially free from seams and from red shortness and to impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleable zone, subjecting samples of said molten mass to a physical test to determine the sufficiency of the aforesaid treating operation, and repeating the aforesaid test after further treatment of said nickel mass with at least one of the aforesaid agents until the nickel mass is rendered, when solidified, substantially free from seams and from red shortness and is rendered malleable from the hot malleable zone to the cold malleable zone.

6. A treated nickel mass having such a constitution as to be malleable from the hot malleable zone to the cold malleable zone and as to possess strength, and rendered substantially free from seams and red shortness and rendered malleable from the hot malleable zone through the conventional red short zone to the cold malleable zone by a controlled and restricted amount of zirconium within a range of about 0.010% to about 0.25% and a member of the group consisting of boron and phosphorus within a range of about 0.003% to about 0.75%.

7. A treated nickel mass having such a constitution as to be malleable from the hot malleable zone to the cold malleable zone and as to possess strength, and rendered substantially free from seams and red shortness and rendered malleable from the hot malleable zone through the conventional red short zone to the cold malleable zone by a controlled and restricted amount of zirconium and a member of the group consisting of .boron and phosphorus, the zirconium, boron and phosphorus being used within a range of about 0.010% .to about 0.25%, about 0.003% to about 0.020%, and about 0.01% to about 0.05%, respectively.

8. The process of treating a mass of malleable nickel and nickel alloys having red shortness to render the same substantially free from seams and from red shortness which comprises subjecting a mass of the aforesaid character while molten to a preliminary treatment with conventional deoxidizing and malleableizing agents including about 0.05 to about 0.20% of aluminum, and about 0.02 to about 0.15% of magnesium to produce a conventionally deoxidized and malleabilized nickel mass possessing conventional red shortness, adding to the thus-treated mass of the aforesaid character while molten a controlled and restricted amount of zirconium and a member of the group consisting of boron and phosphorus to render said mass, when solidified, substantially free from seams and from red shortness and to impart malleability to said nickel mass, when solidified, from the hot malleable zone to the cold malleablev zone, determining the suificiency of the controlled and restricted amount of the agent on test samples by the hammer and an test while the mass is maintained molten, and continuing the aforesaid operations until the hammer and anvil" test determines the suiiiciency oi the.

tional deoxidizing and malleableising agents ineluding aluminum and magnesium to produce a conventionally deoxidisedand malleabilized nickel mass possessing conventional red shortness, treating the thus-treated mass oi the aforesaid character while molten with a controlled and restricted amount oi zirconium and a member of the group consisting of boron and phosphorus to render said mass, when solidifled, substantially free from seams and from red shortneu and to impart malleability to said nickel mass, when solidifled, from the hot malleable zone to the cold malleabie zone. subjecting samples of said molten mass to a physical test to determine the suiliciency oi the aforesaid treating operation, and repeating the aforesaid test after further treatment of said nickel mass with at least one of the aforesaid agents until the nickel mass is rendered, when solidified, substantially tree from seams and from red shortness and is rendered malleable from the hot malleable zone to the cold malleable zone.

10. As an article of manufacture, an improved ductile nickel mass 01' the group of materials consisting oi malleable nickel and malleable nickel alloys having a structure substantially free from defects including seams, cracks and the like and having a constitution resulting from conventional deoxidizing and malleablelzing operations and from asubsequent treatment with a controlled,

restricted and critical amount of zirconium and.

of a member of the group of boron and phosphorus, the said nickel mass being substantially free from conventional red shortness and possessing malleability from the hot malleable zone to and into the cold malleable zone and having been worked through the conventional red short zone at temperatures below about 1600 1". to about 1700 F.

11. As an article of manufacture, an improved ductile nickel mass of the group oi materials connickel mass being substantially free from conventional red shortness and possessing malieability from the hot malleable zone to and into the cold malleable zone and having been worked 1 through the conventional red short zone at temperatures below about 1600" F. to about 1700 F.

12. As an article of manufacture. an improved ductile nickel mass comprising a malleable nickelcopper alloy having a structure substantially free from defects including seams, cracks and the like and having a constitution resulting from conventional deoxidizing and malleableizing operations and irom a subsequent treatment with a controlled, restricted and critical amount of zirconium and of a member of the group consisting of boron and phosphorus, the said nickel mass being substantially free from conventional red shortness and possessing malleability from the hot malleable zone to and into the cold malleable zone and having been worked through the conventional red short zone at temperatures below about 1600 F. to about 1700 F.

13. As an article of manufacture, an improved ductile nickel mass comprising a malleable nickelcopper alloy having a structure substantially tree from defects including seams, cracks and the like and having a constitution resulting from conventional deoxidizing and malleableizing operations and from a subsequent treatment with a controlled, restricted and critical amount 01 zirconium and a member of the group consisting of boron and phosphorus, the said zirconium, boron and phosphorus being used within a range 01' about 0.01% to about 025%, about 0.003% to about 0.020%, and about 0.01% to about 0.05%, respectively, the said nickel mass being substantially tree from conventional red shortness and possessing malleability from the hot malleable zone to and into the cold malleable zone and having been worked through the conventional red short zone at temperatures below about 1600 F. to about 1700 F.

AUGUSTUS ERNEST KAYES.