QUESTION
For high technological industries, you evaluate metals and ceramics beyond the Fe-C alloys to more costly applications.
A.
B.
The figures below give the diffusion coefficients of niobium and silicon in m2/s for alpha- Nb5Si3. and NbSi2.
With the data given in the figure, below, determine the diffusion of Nb within
alpha-Nb5Si3 at 1940°C.
What is the difference in size between NbSi2 and alpha-Nb5Si3 in 10 minutes
within the Nb-Si matrix at 1560 K if the diffused Nb reacts to form the silicides?
Determine the wt%Nb and mass needed to prepare Nb5Si3 for one kg of silicide
– be certain to show any calculations.
From the Al-Cu phase diagram, below, give the three-phase reactions for a eutectic, peritectic, peritectoid, congruent, and euctectoid reactions along with their respective temperatures at which they occur.