A first creep and recovery behaviors of commercial Terylene filament in long duration test for 24 hr were studied under the various loads at 20°C. and 54% RH, and also a second creep and recovery test for 24 hr were made under the same condition. The following results have been recognized;
1) With the exception of the highest load of 3.0g/d, the relationship of strain versus log. (time) is found to be nearly linear in the first and second creep tests, and then the strain rises by increasing the load. On the other hand, total recovery curves are concave to the log. (time) axis under the higher load, and cenvex under the smaller.
2) For the smaller load, initial deformation is larger in first creep than in the first recovery, and for the higher load, its relationship becomes reversed. However it is always larger in the second creep than in the recovery.
3) For the smaller load, the delayd deformation rises slowly as the load is increased, but in the load from 1.0 to 2.5g/d the increased load does not affect it. Fig. (6) shows that the delayed deformation rises rapidly under the highest load of 3.0g/d. It may be attributed to the effect of the flow deformation.
4) On the first and second tests there is a load which minimized the residual deformation, and that of the second test was found smaller. For the some higher load, the recovered specimen's length is shorter than the original, and not contraction is smaller on the second test.
5) Total deformation e is plotted in Fig. (8) according to Andrade's equation [γ=γ
0+β
t1/3]. With the exception of within 3 min. from start, the creep curves to the above formula, The relation between instantaneous elongation γ
0 and the stress is almost linear. Parameter β rises very rapidly as the load is increased on the first creep, and slowly on the second creep. Equation β=β
0sinα
S is found most suitable for the β-
S curves.
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