It depends on the type of agglomeration formed. The metallic particles might form necks with each other being exposed to elevated temperatures and it would be a hard job to deagglomerate them. If agglomerates are weak and loose then you might try dispersing them in some suitable neutral liquid using an ultrasonic bath and then adding an encapsulating agent
I think using argon protection during mixing can be reduced an agglomeration formed
Argon during mixing is OK for protection against oxidation film. However, in many cases powder particles must be passivated by oxide film, for example such pyroforic or water-reactive metals as aluminum or titanium or iron. Therefore oxide film may be necessary. The passivated particles still show agglomeration and should be de-agglomerated before processing.
Argon doesn't help breaking the already existing agglomerates and preventing new agglomeration. Agglomeration may be caused even by Coulomb forces acting between large and small particles and then the particles brought together begin forming metallic bonds (necking). At such a stage only ultrasonic dispersion in a liquid may help to break them apart and then particles should be encapsulated using some organic chemicals. However, the ultrasonic treatment parameters should be chosen carefully to avoid further agglomeration instead of de-agglomeration.
There is a famous technology for powder production by metals desintagration with electric high-voltage discharge. Shock wave generated by dicharge channel can easily desintagrate particles. For high shock-wave pressure it is recommended to make discharges in a condensed medium - water, oil, etc. Here there is the question about chemical reaction between metallic particles and medium.
Electric explosion of wire is carried out in argon and it is very effective way of making metallic nanopowders. To reduce agglomeration they use cooling, passivation and encapsulation
See for example Marat Lerner
I recommend the answer of Mr. Mykhaylo Klymovych Knyazyev
Ineed electric explosion of wires is effective method for production of metallic powders of micro- and nano sizes. And I did pilot tests with copper, aluminium and tungsten wires.
Bu here the task is to desintegrate the aglomeration of microparticles. As to my mind it is better to do it with electric discharge in a chamber filled with a liquid.
It is all the same a matter of cavitation breaking either with ultrasonics or electric discharge. But discharge may cause further densification and welding instead of de-agglomeration. At least the ultrasonics does when power is too much. Aothe effective way of de-agglomeration may be a magnetic blender with needles as breaking bodies
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