this material was the initial motivation for adding fourth order
polynomials, but I could not find a reliable source for the graphs send
to damask@mpie.de. It seems that the CTE levels off for even higher
temperature which calls for a higher order polynomial
- austenitic steel AISI304
- SAE1050 after quenching to martensite
I don't know how the old set of elastic constants for martenstite
(originally coming from 10.1088/0965-0393/23/4/045005) was derived,
but it is hard to believe that the elastic behavior can be that strongly
modified by a heat treatment.