It is common to blend elemental powder and pre-alloyed powder to make new alloys in PM. In case of liquid phase sintering, is it always better to take a MAP whose concentration is more than the solid solubility limit of the alloying element so that we will have more eutectic. Or, do we have eutectic melt formation (from rapidly solidified powder particle) even in lower composition MAP.
Will the alloying element in eutectic within a particle dissolve in matrix?
If elemental powders used, at the contact points of the elements that will form the eutectic phase, the liquid phase will be formed as soon as the eutectic composition is reached.
The same applies to tyre grip on the road, the right proportion must be found between the solid part of the surface and the hollow carved part (which ensures air circulation and consequently the cooling of the material to keep its properties).
if the liquid exceeds the appropriate upper limit, in this case a bad sintering will occur: cracking of the pellet due to the evaporation effect (reduced solid-solid contact surface).
the right proportion means the right amount of liquid to ensure the proper transport of the solid-solid material).
It depends very much on your alloy and on the type of sintering you want to use. For transient liquid phase sintering you can work with MAP additions that will be completely absorbed in the solid solution formed by diffusion. The liquid phase in this case exists only for a short moment. (see project on my researchgate profile).
For sintering with a permanent liquid phase the overall composition (base powder + master alloy) should be in the solid-liquid field of the phase diagramm.
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