Strain-rate enhancement at Dye 3, Greenland

SLOW STRAIN RATE TESTING OF STEEL 14MoV6-3

Slow strain rate test (SSRT) represent a dynamic slowly increasing strain imposed by an external means on uniaxial tension specimen according to ASTM G 129 standard. It is used for relatively rapid screening or comparative evaluation of environmental, processing or metallurgical variables that can affect resistance of material. Testing has been accomplished on low-alloyed boiler steel 14MoV6-3 ...

3 Tunable Dye Lasers

Constraints on the δH diffusion rate in firn from field measurements at Summit, Greenland

We performed detailed H isotope diffusion measurements in the upper 3 m of firn at Summit, Greenland. Using a small snow gun, a thin snow layer was formed from H-enriched water over a 6× 6 m area. We followed the diffusion process, quantified as the increase of the δH diffusion length, over a 4-year period, by retrieving the layer once per year by drilling a firn core and slicing it into 1 cm l...

Solid-state experiments at high pressure and strain rate*

Experiments have been developed using high powered laser facilities to study the response of materials in the solid state under extreme pressures and strain rates. Details of the target and drive development required for solid-state experiments and results from two separate experiments are presented. In the first, thin foils were compressed to a peak pressure of 180 GPa and accelerated. A pre-i...

Global Existence for Rate-Independent Gradient Plasticity at Finite Strain

We provide a global existence result for the time-continuous elastoplasticity problem using the energetic formulation. For this we show that the geometric nonlinearities via the multiplicative decomposition of the strain can be controlled via polyconvexity and a priori stress bounds in terms of the energy density. While temporal oscillations are controlled via the energy dissipation the spatial...