Grain Size•Solid solution•CW•Partial Hardening (Carburization, shot peening)•Video for shot peening: https://www.youtube.com/watch?v=UzTgXpu9_iU

New: Phase Transformation•

Strengthening Mechanisms so far:

Types of Phase Transformations:

Simple diffusion: depends on t and T (e.g. grain growth)1-Complex diffusion (e.g. Eutectoid S→S1+S2)2-No diffusion (not a function of time) happens very fast (e.g Martensitic transformation)

3-

Video 1: freezing of super-cooled water: http://phys.org/news191068504.htmlVideo 2: solidification of Sodium Acetate:https://www.youtube.com/watch?v=ArNfbLvPzYoFrom <https://www.google.com/search?q=rapid+solidification&biw=1280&bih=590&tbm=vid&source=lnms&sa=X&ei=96__VNOlAYHsoATSuYKgAg&ved=0CAgQ_AUoAg&dpr=1.5#q=Sodium+acetate+rapid+solidification&tbm=vid&start=10>

N&G:Nucleation: formation of new phase (Nuclei) Growth: growth of nuclei seed.

Tuesday, October 14, 2014 9:12 AM

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Spheroidite

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Shape Memory Alloy (SMA) demos:http://www.youtube.com/watch?v=JKBM9my5eOAhttp://www.youtube.com/watch?v=mlxrOHD49ZQhttp://www.youtube.com/watch?v=DW4WaTmoZ3chttp://www.youtube.com/watch?v=NcwBTn0zWHwhttp://online.santarosa.edu/homepage/ataiiyan/ (look at link for Perpetual Motion Machines and free energy )

Pasted from <http://online.santarosa.edu/homepage/ataiiyan/>

)

Most widely used TTT diagram for steel is Eutectoid alloy (0.76%C)

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(0.76%C)

Specify the nature of the final product for a small specimen (eutectoid composition) initially Austenized at 750C and has been subjected to the following T-t treatments. Be specific in your answers (e.g. Fine pearlite or

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You will get a take home Q about TTT. Here is solution for parts A and B:

composition) initially Austenized at 750C and has been subjected to the following T-t treatments. Be specific in your answers (e.g. Fine pearlite or Coarse bainite, …..). Include the approximate percentage of each of the components.

A] Cooled rapidly to 500C, Held for 7 second.

B] Cooled rapidly to 300C, held for 10 second.

C] quenched to R.T.

D] re-heated to 600C, held for 1 hr and cooled to RT.

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Omit C.C.T section

you can even "Air Cool" and still get M!

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