#eutectoid

[materialsscienceandengineering]

Fe, C 0.8 (wt%) steel, eutectoid transformation, normalised at 900ºC

Processing Normalised 900 ºC [...] Sample preparation Nital Technique Reflected light microscopy Length bar 400 μm / 100 µm Further information This steel is of the eutectoid composition. Once the temperature is lowered below the eutectoid temperature the steel becomes simultaneously supersaturated with both ferrite and cementite. A eutectoid transformation results (g to a + Fe3C). The resultant microstructure, known as pearlite, comprises lamellae of cementite (dark) embedded in ferrite (white). The platelets are parallel to each other and do not follow a specific crystallographic direction. Contributor Dr R F Cochrane Organisation Department of Materials, University of Leeds

Sources: ( 1 ) ( 2 )

[burakurnaz]

Le de burite, Austenite cementite                   je t’aime                                  je t’aime                                                 je t’aime...

8 saattir şu grafiğe bakınca aşk şiiri bile yazdım ve bir mühendisin aşk şiiri böyle oluyor. grafikten aldığım kelimeleri, bildiğim tek fransızca kelimeyle birleştirip, biraz da şekilli yazınca çok güzel bir aşk şiiri ortaya çıktı. Sevdiceğinize, flörtünüze falan gönderebilirsiniz. Şiirin anlamını sorarsa “eriyorum, içinde çözülmek istiyorum, seni seviyorum...” dersiniz, bunu da uydurdum ama mantık olarak yanlış değil.

ellingham diagram şiirim

[materialsscienceandengineering]

Eutectoid steel, normalised

Composition Fe, C 0.8 (wt%)

[...]

Processing Normalised

[...]

Sample preparation Nital

Technique Reflected light microscopy

Length bar 200 μm / 400 µm / 800 µm

Further information This steel is of the eutectoid composition.  Once the temperature is lowered below the eutectoid temperature the  steel becomes simultaneously supersaturated with both ferrite and  cementite. A eutectoid transformation results (g to a + Fe3C).  The resultant microstructure, known as pearlite, comprises lamellae of  cementite (dark) embedded in ferrite (white). The platelets are parallel  to each other and do not follow a specific crystallographic direction.

Contributor Dr R F Cochrane

Organisation Department of Materials, University of Leeds

Sources: ( 1 ) ( 2 ) ( 3 ) ( 4 )

[materialsscienceandengineering]

What is eutectoid

A eutectoid is a phase transition that involves the transformation of one solid phase into two distinct solid phases. I’ve posted briefly about it before here, but you can also check out this link for more information and another example.

[materialsscienceandengineering]

A eutectoid point ( 2 ) on a phase diagram is an invariant point wherein a single solid solution transforms into two distinct solid solutions, or vice versa. Unlike a eutectic point, none of the phases involved are liquids.

Image source.

[saintcamellia-blog]

I am trying to hurry up and finish my lab report on the heat treatment of steels. This is a x500 magnification of a medium-carbon steel that was slowly air cooled from 950 degrees C. Note the pro-eutecoid ferrite (lighter, 51% by volume) mixed with the darker eutectoid microstructure.

On to more important things:

The other week we had the Presidential Candidate Debate Numero Uno. Obama took what seemed to be a beating by an unexpectedly powerful Romney. I would say that Obama performed decently, and that the perception of his performance was ruined by people’s desire for him to stray from the actual material debate and go onto the path of “47%” and such. The Presidential debates are not the time to be bringing up gaffes, “zingers” or inside jokes to people who have already made up their minds.

The Veep debates, on the other hand? No one cares about these two. Sort of. Enough that we expect them to be a little cheap towards the others running partners.

More interestingly for this election year (similar to the last), we have a candidate KNOWN for saying ridiculous things, and a very green candidate. Who knows when Biden will claim his mother was an unemployed factory worker who was denied coverage for her prostate exams. Additionally, people will probably be waiting for the signs of the large viewing audience to weigh on Ryan. Can he discuss things outside of the budget with a senior opponent?

What do I think we can expect? A dog-pile to the center, just like the first debate because the 50 yard line is apparently the only electable position. Romney, and to some extent Obama spent a lot of time and effort seeming as fringe as possible, just to have to pretend to have the same values when the undecided voters are watching.

Well, I need to wrap up my lab report so I can watch tonight, and have a bit of fun tomorrow. I am analyzing data and micrographs from 11 metallic samples, two aluminum alloys and three steel alloys all treated in different ways. Hope you enjoy one of the few interesting micrographs from this lab! (can't claim all credit for the micrographed, three others in my lab group)