KID4271 thanks man!! Like and subscribe to help me grow channel. Also, let me know what other questions I should do! I try and do one every week or so.
why is it for part C that you identified the purple line as pearlite, and not austenite? I think what happens is that just before the eutectoid temp, what will be produced will be 0.934kg austenite(not pearlite) and 0.066kg Fe3C. After it, there will be 0.831kg a-ferrite and 0.169kg Fe3C as you solved in part B. If you notice the difference between the Fe3C composition before and after the eutectoid temp (0.066-0.169=-0.103), it is 1.03%, so only 0.103kg Fe3C is added/formed! And we can only get Fe3C from austenite. SO, only 0.103kg of austenite actually participated in the eutectoid transformation. And if you notice the difference between the amount of austenite and the amount of pearlite formed before and after the eutectoid temp (0.934-0.831=0.103), it is also 1.03%, thus only 0.103kg austenite transformed to pearlite, and the rest transformed to ferrite. Is my analysis right? Let me know if what I pointed out is right.
It depends on the processing history. Was it cooled slowly quickly rapidly? Was it held at a temperature at any point? Was it annealed? All of these things modify the microstructure. So asking how the microstructure looks at a certain composition and temperature the phase diagrams will only tell us the equilibrium phase fraction, but the processing steps will give us much more insight about the distribution of those phases which is often related to the properties of interest
Eutectoid cementite is basically the Fe3C present in pearlite. we can just get it by removing the pro eutectoid (which is cementite in this case) from the total cementite value we got
Good question. we know that after the material undergoes the eutectoid reaction all of the austinite is converted to a mixture of pearlite and cementite. This happens relatively quickly and so it forms the lamellar structure which we would call pearlite. It's possible to form proeutectoid phases though, such as proeutectoid ferrite or proeutectoid cement.
Thanks a lot, I never quite understood what the diagram was actually used for
You almost sound like Edward Norton. Good video. It helped me with my homework
Just made my day :)
Your videos are awesome! Just wanted to let you know brotha.
KID4271 thanks man!! Like and subscribe to help me grow channel. Also, let me know what other questions I should do! I try and do one every week or so.
Thank you For this video.. Very helpfully ❤️
thank you so much, excellent explanation
Great video man!! Thank you very much!!!
why is it for part C that you identified the purple line as pearlite, and not austenite?
I think what happens is that just before the eutectoid temp, what will be produced will be 0.934kg austenite(not pearlite) and 0.066kg Fe3C. After it, there will be 0.831kg a-ferrite and 0.169kg Fe3C as you solved in part B.
If you notice the difference between the Fe3C composition before and after the eutectoid temp (0.066-0.169=-0.103), it is 1.03%, so only 0.103kg Fe3C is added/formed! And we can only get Fe3C from austenite. SO, only 0.103kg of austenite actually participated in the eutectoid transformation.
And if you notice the difference between the amount of austenite and the amount of pearlite formed before and after the eutectoid temp (0.934-0.831=0.103), it is also 1.03%, thus only 0.103kg austenite transformed to pearlite, and the rest transformed to ferrite.
Is my analysis right? Let me know if what I pointed out is right.
Thank you Very much
Great video, I have a question how do the microstructures look like if for example at 5wt%C it's cooled to 700°C
It depends on the processing history. Was it cooled slowly quickly rapidly? Was it held at a temperature at any point? Was it annealed? All of these things modify the microstructure. So asking how the microstructure looks at a certain composition and temperature the phase diagrams will only tell us the equilibrium phase fraction, but the processing steps will give us much more insight about the distribution of those phases which is often related to the properties of interest
Hi great video, also what would you do if you were asked to figure out the amount of eutectoid cementite?
Eutectoid cementite is basically the Fe3C present in pearlite. we can just get it by removing the pro eutectoid (which is cementite in this case) from the total cementite value we got
Cool! Thank you!
could you please make a video of the lever rule with different examples. thank you
Great video! For part c), is asking for the wt% of pearlite and cementite the same as asking for austenite and cementite?
Good question. we know that after the material undergoes the eutectoid reaction all of the austinite is converted to a mixture of pearlite and cementite. This happens relatively quickly and so it forms the lamellar structure which we would call pearlite. It's possible to form proeutectoid phases though, such as proeutectoid ferrite or proeutectoid cement.
Sir, I got a question, how pro-eutectoid cementite is different from normal cementite?
Proeutectic will be present in larger globs as opposed to eutectoid which will be present in lamellar structure.
helped thanks
thanks
Lol the duration of this video is 7:27 😂
I don't get it. Is that surprising?
727 degree C - Eutectoid temperature in Fe-C system.
@@thebluedragon6385 lol. Illuminati 👁️