C.P. No. 1367 PROCUREMENT EXECUTIVE, MINISTRY OF DEFENCE
نویسنده
چکیده
SUMMARY c The concept that creep response is the result of a transient approach to a minimum strain rate continuously modified by accumulating damage has been investigated using high precision creep data. It was considered that the accumulated creep strain might be some measure of internal damage and curves of log creep strain rate against creep strain are shown to exhibit linearity at higher strain levels consistent with these assumptions. A modified 'steady-state' relationship has been derived and the variation of its two coefficients with stress and temperature explored. The effect of load and temperature history is illustrated by varying the prior heating time, by cyclic load testing and by step reductions in load level, and it is tentatively concluded that tests of these types may be correlated with the appropriate continuous creep test by using the modified 'steady-state' relationship with corrections for differences in accumulated creep strain and time at temperature.
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