A grain-size driven transition in the deformation mechanism in slow snow compression

Description

We conducted consecutive loading-relaxation experiments at low strain rates to study the viscoplastic behavior of the intact ice matrix in snow. The experiments were conducted using a micro-compression stage within the X-ray tomography scanner in the SLF cold laboratory. Next, to evaluate the experiments, a novel, implicit solution of a transient scalar model was developed to estimate the stress exponent and time scales in the effective creep relation (Glen's law). The result reveals that, for the first time, a transition in the exponent in Glen's law depends on geometrical grain size. A cross-over of stress exponent $n=1.9$ for fine grains to $n=4.4$ for coarse grains is interpreted as a transition from grain boundary sliding to dislocation creep. The dataset includes compression force data from 11 experiments and corresponding 3D image data from tomography scans.

Resources

Name Format Description Link
57 https://www.envidat.ch/dataset/slow-snow-compression/resource/faca29b9-a95f-4f86-a3f9-1bf7faedab29
74 https://www.envidat.ch/dataset/slow-snow-compression/resource/a23d3947-513f-47dc-aba2-a56fd8b4afcf
57 https://www.envidat.ch/dataset/slow-snow-compression/resource/faca29b9-a95f-4f86-a3f9-1bf7faedab29
74 https://www.envidat.ch/dataset/slow-snow-compression/resource/a23d3947-513f-47dc-aba2-a56fd8b4afcf
57 https://www.envidat.ch/dataset/slow-snow-compression/resource/faca29b9-a95f-4f86-a3f9-1bf7faedab29
74 https://www.envidat.ch/dataset/slow-snow-compression/resource/a23d3947-513f-47dc-aba2-a56fd8b4afcf

Tags

  • microstructure
  • snow-mechanics
  • slow-snow-compression-experiments
  • x-ray-tomography
  • ice

Topics

  • EDUC

Categories