Decomposition of solute concentration in Fe-Cr-C alloy

[Prithivirajan]

Say, I have a 0.1 % C and 18 % Cr in a Fe-alloy. At a particular temperature, we have precipitate formation (of Cr23C6), eating many Cr atoms. At a given temperature , How do I evaluate the remaining Cr atoms in the alloy ?

 

The rest of the Cr atoms will be just fine. They are not the weak link.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[EdStainless]

Convert to atomic percent, multiply C x 23/6 to figure out how much Cr is tied up.
The subtract from the original C and convert back to wt%.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

I've done that math previously, and a little C can tie up a whole lot of Cr in terms of percent mass!

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[EdStainless]

So roughly 52/12 x 010 = 0.43 wt % Cr

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

0.10 x 23/6 x 52/12 = 1.66

(wt% C x Atomic ratio x Atomic weight ratio = wt% Cr)

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[EdStainless]

duh, thanks IM.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

First thing I've ever seen you get wrong, Ed!

(It's always the simplest question on the exam I screw up.)

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."