In many papers about high entropy alloys it was stated that no segregation exist and it has demonstrated by EDS and APT analysis,however the reason has not mentioned.For comparison we have elemental segregation in advanced high strength steels and it effects mechanical behavior.but it seems different in some high entropy alloys
Maybe they were using a Powder Metallurgy methods. I've seen some articles where segregation occured in casted HEAs.
As the name suggests, High-Entropy Alloys (HEA) are multiple component concentrated solid solutions occurring as single phase solid solutions (mostly in face-centred cubic or body-centred cubic forms). The lack of segregation in such alloys has been attributed to the high configurational entropy of such systems.
Dear Hasanpour;
The previous answers are correct, moreover there can be another reasons such as enthalpies of mixing and cooling rates. Most of elements alloyed are transition metals and their mixing enthalpies are very low, near zero. It means that the "perfect" solid solution formation is more common than segregation in several phases. The high cooling rates (usually water refrigerated copper molds in the as cast alloys) avoid the diffusion of elements in the alloy ("freezing" the alloy in solid solution structure), which added to the effect of sluggish diffusion can provide answers to your question.
To sum up,check the cooling rates of the papers studied and compare with the cooling rates of the advanced steels. The thermodinamic parameters are not the only guides in High entropy alloys,also kinetic paramaters should be taken into account.
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