I want to ask to everyone.
Why when gamma prime forming element is added more, gamma formation temperature is decreased?
What can be relationship in there?
Hi,
the materials I investigated (60-0% gamma prime, rest gamma) showed than the amount of gamma prime in chemical equilibrium decreases with increasing temperature (in the range 500-1000°C) and consequently the amount of gamma increases.
I dont know which materials in wihich temperature range you investigate, but generally beside the gamma prime formers there are also elements which might destabilize gamma prime and/or stabilize other phases, which can change the chemical equilibrium thus the amount of gamma and gamma prime.
Best regards
Thanks for answer.
That means, gamma prime former element may destabilize the gamma prime or other phases which are affected by Ni, Al of Ti.
And also, the amount of gamma prime phase decreases with increasing temperature.
However, in case of Ta, Ta is gamma prime forming element and it affects the gamma prime formation temperature as increased because Ta is refractory element which means high melting element.
Thereby, gamma prime volume fraction was increased by Ta as shown in some paper.
This means that gamma prime forming element can increase the formation temperature of gamma prime phase if that elements have high melting point.
Also, forming element means, if some element is solve in gamma prime, because of activation energy for increased nucleation sites, formation temperature should be increased.
Thereby, I think forming element increases the formation temperature.
Isn't it right?
Hi,
sorry, could you please explain what do you mean by "gamma prime forming element may destabilizes gamma prime"?
Basically, it always depends on which range of concentration you are investigating. If one assumes (Example 1) 100%Ni and you add a certain amount of Al, Ti or Ta at a specific temperature gamma prime can be formed. If you have(Example 2) Ni-25 at.-%Al, namely the composition of gamma prime, and you add some more Al the amount (relative amount in %) of gamma prime should decrease. Maybe you mean this?
In example 1 gamma prime volume fraction is increased by addition of gamma prime forming elements. However, I am not sure about the effects of melting points. In my experiments (similar to example 1) I found gamma prime to be stable at higher temperatures when the amount of gamma prime forming elements (here Al) is higher.
Hope this helps. Best regards
Hi,
Would you explain this why for example adding more Al, will decrease gamma prime fractions of the alloy?
Thanks
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