Experimentation resulted in an improved levitation-melting technique for metals and alloys which quickly produces a completly homogeneous melt. Also developed were two levitation coils that permit a wide variety of metals to be levitated in the molten state and a helium quenching method which minimizes contamination and segregation

Downey, J. W.

English

NASA Technical Reports Server

January 1969	 Brief 69-10006 
•	 AEC-NASA TECH BRIEF 
AEC-NASA Tech Briefs describe innovations resulting from the research and development program 
of the U.S. AEC or from AEC-NASA interagency efforts. They are issued to encourage commercial 
application. Tech Briefs are published by NASA and may be purchased, at 15 cents each, from 
the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia 22151. 
Levitation-Melting Technique for Metals and Alloys 
Experimentation at Argonne National Laboratory 
has led to improved techniques for levitation melting 
of special metals, alloys, and intermetallic compounds, 
along with designs for two levitation coils and a tech-
nique for helium quenching. The greatest hindrance to 
the use of levitation melting has been the lack of 
available information on levitation coil designs. 
Levitation melting is a recent technique for melt-
ing metallic materials by suspension of the dense 
charge in space with an electromagnetic field. The 
main advantage of this method for preparing alloys is 
that a completely homogeneous melt can be produced 
quickly. Other attractive features of this technique 
are: (I) The molten charge can be solidified while 
levitated to minimize contamination by direct contact 
with other materials. (2) Alloys with a specific shape 
can be achieved directly by dropping the molten 
charge into a preshaped mold. (3) The specimen can 
be rapidly cooled, minimizing the amount of segre-
gation upon solidification. 
This investigation had the following objectives: 
(I) to develop levitation coils capable of melting a 
wide variety of metals and alloys, especially the transi-
tion-metal alloys; (2) to cast alloys into specific shapes 
directly from the molten state, particularly brittle in-
termetallic compounds not amenable to conventional 
shaping techniques; and (3) to develop a gas-quench-
ing technique so that high-purity alloys in the liquid 
state could be quenched to the solid state without 
contamination. 
Two coil configurations were developed that permit 
a wide variety of metals to be levitated successfully 
in the molten state. Although only limited quantities 
of material may be processed with the present coils, 
the quantities are adequate for research purposes. 
While the two coils resemble previous designs, the
overall dimensions were increased to allow for larger 
charges. Also, the size of the copper tubing was in-
creased to provide a greater cooling capacity. 
In the study, various techniques were developed 
that are unique to this method of alloy preparation. 
A helium-gas-quenching method is described that 
minimizes contamination and segregation. The helium 
gas is precooled with liquid nitrogen to provide a 
faster quenching rate. Aluminum and pure metals with 
higher melting points, such as zirconium, titanium, 
and vanadium, have been quenched to solid state by 
this technique. 
It was found that the levitating-melting technique is 
an ideal method for the preparation of alloys for 
Mossbauer studies, which require the addition of a 
small quantity of a specific isotope. For example, 
small quantities of Fe57
 were successfully added to 
vanadium and palladium to produce a homogeneous 
distribution of the isotope. 
Various solid-solution and intermetallic com-
pounds were prepared. The levitation melting 
produced homogeneous alloys unobtainable by non-
consumable arc-melting techniques. 
Notes: 
I. Details are given in a report, "Levitation Melting 
of Metals and Alloys," by J. W. Downey, ANL-
7398, December 1967, available from the Clearing-
house for Federal Scientific and Technical 
Information, Springfield, Virginia 22151 for $3.00 
(microfiche copies, $0.65). 
2. Levitation melting has been used for numerous 
purposes including alloy preparation, vaporiza-
tion studies, determination of the densities of liquid 
metals, and determination of the thermodynamic 
properties of alloys.
(continued overleaf) 
This document was prepared under the sponsorship of the Atomic liability resulting from the use of the information contained in this 
Energy Commission and/or the National Aeronautics and Space document, or warrants that the use of any information, apparatus, 
Administration. Neither the United States Government nor any per- method, or process disclosed in this document may not infringe pri-
son acting on behalf of the United States Government assumes any vately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19690000006 2020-03-16T17:29:43+00:00Z
3. The information may be of interest to research 
metallurgists. 
4. Inquiries concerning this innovation may be di-
rected to:
Office of Industrial Cooperation 
Argonne National Laboratory 
9700 South Cass Avenue 
Argonne, Illinois 60430 
Reference: B69-10006 
Source: J. W. Downey
Metallurgy Division
Argonne National Laboratory
(ARG- 10240)
Patent status: 
Inquiries about obtaining rights for commercial use 
of this innovation may be made to: 
Mr. George H. Lee, Chief 
Chicago Patent Group 
U.S. Atomic Energy Commission 
Chicago Operations Office 
9800 South Cass Avenue 
Argonne, Illinois 60439 
Brief 69-10006
	 Category 03	
•


Levitation-melting technique for metals and alloys

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