Accession Number : ADA018015

Title :   Work-Hardening and Strain Rate Sensitivity of Flow Stress in High Purity Ice Single Crystals.

Descriptive Note : Research rept.,

Corporate Author : COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H

Personal Author(s) : Parameswaran,V. R.

Report Date : OCT 1975

Pagination or Media Count : 16

Abstract : Single crystals of high purity ice deformed by uniaxial compression on an Instron machine showed remarkable work- hardening after about 8% strain. By changing the strain rate during compression tests in the plastic region of the stress-strain curve, an apparent activation volume V* and a dislocation mobility exponent m were calculated from the strain rate sensitivity of flow stress. The large work-hardening and the rapid increase in the value of m beyond about 10% strain indicate that the plastic flow in this region is controlled by dislocation intersections and nonconservative motion of jogs. (Author)

Descriptors :   *Single crystals, *Ice, Strain rate, High purity, Dislocations, Hardening, Hardness, Motion, Plastic properties, Laboratory tests, Flow, Compression

Subject Categories : Snow, Ice and Permafrost
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE