hello! around 49:00, when the professor is mentioning about "uphill diffusion", did he not mistakenly switch the Si content for cast iron and steel? (As in, the steel (C 0.4 wt%) side should have more Si (~2%) while the cast iron (C 3.0 wt%) side should have less Si (0%) ) and about Si reducing the activity of carbon... I hope someone could help me with this last part.
+apollosauce no,cast iron is a ternary alloy that needs 2% silicon for carbon partition from austenite. steel on the other hand may or may not need silicon. depending on the application
if you will think logically about the locking of carbon in cast iron, you need si in it. if you add higher amount of si in steel, more locking will happen in steel ,as a result activity of carbon will be lower in steel resulting in diffusion of carbon from cast iron to steel. but this is not the case. I think i am able to help u
@@akashkumarsingh2553 Thank you all for your explanations. But I was confused about the professor's explanation of "uphill diffusion" when he said that Si in steel (or cast iron) reduces the activity of C. I was confused because my understanding was that Si in iron increases(not reduce) the activity of carbon as explained in a textbook I read: [TRANSPORT PHENOMENA IN METALLURGY by Geiger and Poirier, p444] It's a very old textbook I picked up from a pile of books being thrown away so maybe the concept or even the whole book is outdated and invalid at this point. The uphill diffusion part is only explained briefly in this book and quotes the experiment paper by Darken in Trans. AIME(1948)
This professor is knowledgeable and his lecture is thought-provoking. Very good professor!
Just absolutely incredible. They deserve awards for this level of teaching
wow, thermodynamics can be so interesting
Another great lecture, thank you !
Very best lecture 👍
Please make a course on basics of metallurgical thermodynamics
@12:30 Mg2Si has melting point is not greater than both pure metals.......its less than silicon melting point.
hello! around 49:00, when the professor is mentioning about "uphill diffusion",
did he not mistakenly switch the Si content for cast iron and steel?
(As in, the steel (C 0.4 wt%) side should have more Si (~2%) while the cast iron (C 3.0 wt%) side
should have less Si (0%) )
and about Si reducing the activity of carbon... I hope someone could help me with this last part.
+apollosauce no,cast iron is a ternary alloy that needs 2% silicon for carbon partition from austenite. steel on the other hand may or may not need silicon. depending on the application
if you will think logically about the locking of carbon in cast iron, you need si in it. if you add higher amount of si in steel, more locking will happen in steel ,as a result activity of carbon will be lower in steel resulting in diffusion of carbon from cast iron to steel. but this is not the case. I think i am able to help u
Yes , you are right .
@@akashkumarsingh2553 Thank you all for your explanations. But I was confused about the professor's explanation of "uphill diffusion" when he said that Si in steel (or cast iron) reduces the activity of C. I was confused because my understanding was that Si in iron increases(not reduce) the activity of carbon as explained in a textbook I read: [TRANSPORT PHENOMENA IN METALLURGY by Geiger and Poirier, p444] It's a very old textbook I picked up from a pile of books being thrown away so maybe the concept or even the whole book is outdated and invalid at this point. The uphill diffusion part is only explained briefly in this book and quotes the experiment paper by Darken in Trans. AIME(1948)
Tooooooooooooooooooooooop cours merci beaucoup monsieur
my mind completely messed up #watching 1st time