THE EFFECT OF TEMPERATURE ON THE YIELD STRENGTH FOR BASAL SLIP IN LITHIUM ALPHA SOLID SOLUTION OF MAGNESIUM SINGLE CRYSTALS
Abstract
An investigation was conducted on the deformation of single crystals of alpha solid solution (12.5 at-% Li in Mg) specially oriented for basal slip. Crystals were tested in tension over the range of temperatures between 77 and 645 K. The alloy has a critical resolved shear-stress at least ten times that of pure Mg. Whereas the critical resolved shear-stress was temperature dependent below 250 K, it was relatively constant over the higher temperature range. Above 400 K all crystals fractured on the prismatic planes following duplex prismatic slip. Twinning, kinking and accommodation bending was observed in areas adjacent to subgrain boundaries and the shear-stress vs shear-strain curves for the crystals were correlated with the various types of deformation markings observed on the surfaces of the strain specimens. The thermally activated deformation mechanism below 250 K probably arises from the dislocation intersection process whereas the higher temperature athermal behavior is thought to be a result of short-range ordering. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 15, 1961
- Accession Number
- AD0265117
Entities
People
- J.d. Mote
- J.e. Dorn
- R.m. Quimby
Organizations
- Materials Research Laboratory