15 research outputs found
The mid-infrared instrument for the James Webb space telescope, II: design and build
Instrumentatio
Rhizosphere and endophytic bacteria for induction of salt tolerance in gladiolus grown in sodic soils
Effects of Duty Cycle on Texture Orientation and Composition of TiCx Nanostructured coatings
Influence of Experimental Parameters on Fracture Toughness of Ceramics Measured by Different Techniques
What’s Old and What’s New in Concepts of Induced Systemic Resistance in Plants, and its Application
Dynamic shearing resistance of molten metal films under high pressures and extremely high shearing rates
Plastic Deformation of Hafnium under Uniaxial Compression
The plastic behavior of polycrystalline hafnium (Hf) was investigated over a range of strain rates under uniaxial compression. Hafnium exhibited considerable ductility and a moderately rate-sensitive plastic behavior. The stress-strain response consisted of initial yielding followed by parabolic hardening. Microstructural observations on quasistatically deformed specimens revealed that yielding occurred by dislocation activity and that hardening was dominated by twinning on {1012} planes and by slip/twin interactions. A considerable reduction in dislocation and twinning activity was observed in specimens deformed at high strain rates. Failure occurred by shear localization and void growth and coalescence within the shear bands. Measurement of the temperature rise during high strain rate deformation was also made. From these measurements, the fraction of work converted to heat as a function of strain was determined and found to decrease with increasing strain