Perlite an Ferrite grains- HSC. ASAP (1 Viewer)

vitamin D

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what are they both, and what happens to a substance when pearlite or ferrite grains are stressed or unstressed ? or when one is stressed and the other is not??
 
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keepLooking

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Full anealing will produce equiaxed unstressed grains of ferrite and pearlite.
Process annealing will produce equiaxed unstressed ferrite grains but leaves pearlite in its stressed state.
[From Stephen Payne's notes]

I am assuming the state of the grains will affect the mechanical properties as for specifics, I have no idea ;)
 

vitamin D

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Full anealing will produce equiaxed unstressed grains of ferrite and pearlite.
Process annealing will produce equiaxed unstressed ferrite grains but leaves pearlite in its stressed state.
[From Stephen Payne's notes]

I am assuming the state of the grains will affect the mechanical properties as for specifics, I have no idea ;)
i use his notes too, but i stil dont get what pearlite and ferrite grains are :/
 

astroman

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Normalising is the process of raising the temperature to over 60ºC into the austenite range. It is held at this temperature to fully convert the structure into austenite, and then removed form the furnace and cooled at room temperature under natural convection. This results in a grain structure of fine pearlite with excess of ferrite or cementite.
 

vitamin D

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Normalising is the process of raising the temperature to over 60ºC into the austenite range. It is held at this temperature to fully convert the structure into austenite, and then removed form the furnace and cooled at room temperature under natural convection. This results in a grain structure of fine pearlite with excess of ferrite or cementite.
what is the effect of this ?
 

nobody

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ferrite is soft, and malleable
pearlite is generally stronger, as it is a laminate of both ferrite and cementite

Also im pretty sure its not 60ºC..



EDIT: i is stupid. swapped ferrite and pearlite. go listen to post below
 
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keepLooking

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when a grain is stressed, its softer ? confirm plz
I think you could just say that?
(Stressed grains make the material more brittle, I think)

Also,
Pearlite is a combination of ferrite and cementite.
Ferrite is iron with 0.008% carbon and is a soft, ductile material.
Cementite is iron with 6.67% carbon and is quite hard and brittle.
[OTEN notes]
 
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vitamin D

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I think you could just say that?
(Stressed grains make the material more brittle, I think)

Also,
Pearlite is a combination of ferrite and cementite.
Ferrite is iron with 0.008% carbon and is a soft, ductile material.
Cementite is iron with 6.67% carbon and is quite hard and brittle.
[OTEN notes]
im so fucked for those questions like this in the exam. do you have a specific summary or anything where i can rote learn this shyt
 

astroman

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im so fucked for those questions like this in the exam. do you have a specific summary or anything where i can rote learn this shyt
I doubt you will have to be that specific for these types of questions.
 

vitamin D

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lol, just so you guys know: First half is dot points of all modules and 2nd half is a in depth summary of all cores. I was confused af when i got them :)
 
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keepLooking

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lol, just so you guys know: First half is dot points of all modules and 2nd half is a in depth summary of all cores. I was confused af when i got them :)
If you didn't tell me, I wouldn't have realised haha.
 

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