The Influence of Ice-Crystal Size on Creep
Abstract Uniaxial compression tests were conducted on polycrystalline-ice samples with random c -axis orientation and steady-state creep rates were determined. Experiments were conducted on both inclusion-bearing and inclusion-free ice and were run at constant stress and constant temperature. During...
Published in: | Journal of Glaciology |
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Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1978
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Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0022143000033633 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000033633 |
Summary: | Abstract Uniaxial compression tests were conducted on polycrystalline-ice samples with random c -axis orientation and steady-state creep rates were determined. Experiments were conducted on both inclusion-bearing and inclusion-free ice and were run at constant stress and constant temperature. During freezing, the presence of inclusions in low concentrations inhibits crystal growth; variations in the volume-fraction of inclusions thus result in variations in ice-crystal size. The creep rate of polycrystalline ice at high temperatures and moderate stresses is extremely sensitive to variations in ice-crystal size. Due to an apparent inversion between dislocation-controlled creep and diffusion-controlled creep, the optimum grain size for creep resistance is about 1.0 mm. Increasing or decreasing the average crystal size from this critical value results in an increase in secondary-creep rate. |
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