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Thread: Avrami equation help

  1. #1
    Associate Engineer
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    Avrami equation help

    Good evening

    I am after some help. I have a set of tensile results that I need to produce a graph using the avrami equation. Would somebody be able to give me some tips of where to start. I cant figure out how the results would fit into the equation

    kind regards
    James

  2. #2
    Lead Engineer Cake of Doom's Avatar
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    The JMAK gives you the fraction of transformation and a time interval so, I suppose, an x-y type of graph could be the simplest form.

  3. #3
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    Thanks for you reply, I am just unsure how to go about this, I obviously have time / load / extension for the tensile test.

    How does this fit into the avrami equation y=1-e^kt(^n)? I 'm guessin t=time, y=extension, if that's right how do I find K & n?

    thanks
    James

  4. #4
    Kelly_Bramble's Avatar
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    If you have test data just create a x and y column then a line graph in excel. The Avrami Equation will normalize the selected data given not report exact data.

  5. #5
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    so the x / y graph would be stress strain as per normal way to show tensile results? As the avrami is fraction of transformation vs growth (nucleation). How do I change a graph to show this if that's the case?

    regards
    James

  6. #6
    Kelly_Bramble's Avatar
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    You need a sufficient number of x y data for the stress train curve.. That's all - extrapolation should be OK for gap in the data.

  7. #7
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    is this not what a avrami curve is? if so how do you convert stress/strain to this? Unless I've got it completely wrong.

    regards
    James
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