<DOC>
<DOCNO>
867
</DOCNO>
<TITLE>
low frequency fatigue of nimonic 90 . low frequency
fatigue - a rheological approach .
</TITLE>
<AUTHOR>
landau,c.s.
</AUTHOR>
<BIBLIO>
engineer, 213, 1962, 911.
</BIBLIO>
<TEXT>
an alloy of nimonic 90 type has been tested under cyclic loads at
temperatures of 800 deg., 850 deg. and 900 deg. cent .  graham's
descriptive theory of deformation has been developed in detail for the
tests reported here, and shown to provide a satisfactory description of
the experimental results .  the variation of cumulative strain with
number of cycles can be described by the sum of powers of cycle number,
n, n, n, and n .  there is qualitative agreement between the observed
and the calculated stress-strain loops .  the effect of variation of
maximum stress per cycle can be described by the sum of power terms with
simple exponents .  within the scatter of observation, the total time to
fracture is independent of the frequency .
</TEXT>
</DOC>
