Annealing and Mechanical Properties of ECAP Tantalum
Abstract
Equal Channel Angular Pressing (ECAP) was used to breakdown the microstructure of tantalum rods produced by Cabot and H.C. Starck. Hardness measurements from annealing samples showed a 100 degree C to 150 degree C difference in the softening response to recrystallization for the two manufacturers. Orientation maps were generated from the samples to characterize the thermo-mechanical processing and texture evolution. Low temperature annealing resulted in a fine grain size that was uniform. In the higher temperature anneals, the grain size varied with location. Mechanical property measurements showed the strength of the hardened tantalum to be 800MPa. Taylor Impact experiments were used to study the behavior of tantalum under dynamic loading. The plastic flow in the recovered Taylor Impact specimen was analyzed to determine the rotation that accompanied the texture evolution. The mechanical property data was used to calibrate the MTS constitutive model. The Taylor Impact experiment was simulated using the MTS constitutive relationship and an anisotropic yield surface. These calculations were in excellent agreement with the experimental data.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2011
- Accession Number
- ADA540793
Entities
People
- James O'brien
- Joel House
- John Bingert
- Michael Nixon
- Philip Flater
- Richard Harris
- Robert De Angelis
Organizations
- Air Force Research Laboratory