Measuring and testing – Liquid analysis or analysis of the suspension of solids in a... – Content or effect of a constituent of a liquid mixture
Patent
1997-07-25
1999-04-13
Brock, Michael
Measuring and testing
Liquid analysis or analysis of the suspension of solids in a...
Content or effect of a constituent of a liquid mixture
73 6141, 266236, 75407, G01N 3320, C22B 902
Patent
active
058940855
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a method and to apparatus for determining the purity of a metal alloy.
More precisely, the invention relates to determining whether the concentration of impurities in a metal alloy, and in particular the concentration of oxides that result from making the alloy is unacceptable, acceptable, or very low so as to be able to determine whether the alloy in question is usable or not. This problem arises in particular, but not exclusively, with aluminum alloys.
These impurities that result from making the alloy, in particular an aluminum alloy, may consist essentially in oxides. Nevertheless, it is also possible to find salts, carbides, nitrides, borides, and sludge in the form of particles or of a kind of skin that forms on the alloy.
It will be understood that it is necessary, or at least desirable, once an alloy has been made, to ensure that it does not include too high a content of impurities, which could make use of the alloy difficult or impossible for making certain types of part subjected to high mechanical stresses.
Various methods have been used for determining impurity content. These various methods comprise: spectroscopic emission; various types of chemical analysis, e.g. gas chromatography; another type of measurement is volumetric analysis using centrifuging or filtering techniques; and then there are non-destructive techniques, such as using ultrasound or techniques based on using X-rays.
In the filter group of techniques, mention can be made in particular of the ALCAN method known under the name PODFA which is based on the following principles: about 2 kg of alloy are taken directly while in molten form. This alloy to be tested is caused to pass through a filter. The residue in the filter is then selected vertically along the central plane and prepared for metallographic analysis. The analysis makes it possible to determine the concentration of impurities or inclusions expressed in mm.sup.2 /kg. To cause the alloy to pass through the filter, it is necessary to apply air at sufficient pressure onto the free surface of the alloy in the receptacle which contains it.
However, it will be understood that that filter-based technique requires subsequent metallographic analysis, which takes a certain amount of time, and which therefore means that genuinely instantaneous analysis cannot be provided while the alloy is being made.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method and an apparatus for determining impurities in a metal alloy that enable such determination to be performed quickly and continuously while the alloy is being made.
To achieve this aim, the apparatus for determining the purity of a metal alloy is characterized in that it comprises: axis having an open top end and a bottom end defining an orifice of small dimensions; temperature; said receptacle, said quantity of alloy initially being at a second predetermined temperature, whereby said alloy flows under gravity alone through said filter until the filter becomes clogged by the impurities contained in said alloy; and through said filter prior to it becoming clogged by the impurities contained in the alloy, whereby the purity of said alloy is deduced.
It will be understood that implementing the above apparatus is very simple since it suffices to take a sample from the alloy while it is being made, to put the sample in the receptacle closed by the filter, and to use any appropriate means for measuring the quantity of alloy that possess through the filter before it becomes clogged by the impurities, it being understood that the shell constituting the receptacle is maintained at a predetermined temperature.
In a preferred implementation of the invention, for an aluminum alloy, the filter is an extruded ceramic filter. Also preferably, the filter has porosity of about 300 cells per square inch (CSI).
Also preferably, the apparatus for determining the purity of the alloy is mounted on a moving carriage. The shell and a pan for recovering the alloy
REFERENCES:
patent: 5095740 (1992-03-01), Hodgson et al.
Lessiter et al. To Pour or not to Pour: The Dilemma of Assessing Your Aluminum Melt's Cleanliness, Modern Casting, pp. 45-48, Feb. 1996.
S. Ali, et al., "Physical Refining of Steel Melts by Filtration", Metallurgical Transactions/B: Process Metallurgy, vol. 16B, Nos. 1-4, Dec. 1985, pp. 725-742.
Richard Michel
Roberge Jean-Luc
Brock Michael
Centre Technique des Industries de la Fonderie
LandOfFree
Device for determining the purity of a metal alloy does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for determining the purity of a metal alloy, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for determining the purity of a metal alloy will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-223929