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Lattice constant of martensite?

  1. Jul 1, 2008 #1
    Hi everyone-

    I am trying to run some MD simulations of martensitic iron. I am having a lot of trouble finding a lattice constant anywhere in the literature... I know the crystal structure is bct, so there will be some c/a ratio as well... any suggestions?

  2. jcsd
  3. Jul 2, 2008 #2
    I have done a little bit more research... but I am not well versed enough in steels to figure out if what I am saying is true.

    I want to research the transition from austenite (fcc) to martensite. The potential I am using was written for ferrite (bcc), with a lattice constant of 2.8553, but I think it will still be stable for austentite. Doing a lowest energy calculation, I figured out the lattice constant for fcc is about 3.66.

    Now, if I am simulating pure Fe, with no carbon, is it correct that the martensite will have a bcc configuration? I believe the bct deformation is caused by carbon atoms not fitting in properly... if so, then I can create an interface between some fcc and bcc, and let it run, and this would effectively simulate a austenitic/martensitic boundary. Does this seem correct?
  4. Jul 2, 2008 #3


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    I don't think you will find a useful c/a in literature because this is a strong function of composition and heat treatment (which means there's non-equilibrium weirdness hidden in it - probably from diffusion of C)!

    The authoritative reference is supposed to be: Wechsler, M. S., Lieberman, D. S., and Read, T. A., β€œOn the Theory of the Formation of Martensite,” AIME Trans. J. Metals 197, 1503 (1953).

    If that's hard to access, try: S. Lieberman, M. S. Wechsler, and T. A. Read, J. Appl. Phys. 26, 473 (1955)
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