Thermal cycling creep in molybdenum single crystals

Thermal cycling creep has been observed in thin single crystalline molybdenum foils heated by self resistance heating. It was possible to seperate the total creep strain into two components: the first one involved ordinary viscous creep (i.e. the creep strain was proportional to the time, during which the sample experienced the creep temperature), while the second component increased monotonously with the number of the thermal cycles (i.e. it was due to thermal cycling creep). The results are rationalized in terms of the relaxation of thermal stresses connected with the large temperature gradients at the grips. 6 refs., 6 figs. (Author)