Dear Meysam,

I don't understand what's is the question. Solid solubility between Al and Ni depends of composition and temperature. According with the phase diagram, at 300K the B2_BCC phase has a existence field that is lower that at high temperatures. It is very common behavior. As example, there is more solubility of salt (or sugar) in water at high temperatures than at ambient conditions.

If you have any question please do not hesitate to contact me.

Best regards

Pedro

Dear Meysam,

The question is not clear enough. If you ask how the “width“ of NiAl (B2) region at the binary diagram depends on additional alloying element, you should consider a ternary phase diagram. In the case of multi-alloying, you need to look for the information in relevant published scientific papers or perform your own research. If you need any help in discussion, please contact me.

Not necessarily, it depends on other factors such as the degree of subcooling, the content of impurities, etc.