Tungsten-steel metal matrix composites are consolidated using electro-discharge sintering. At first steel and tungsten powders sintered separately then 25 vol% W, 50 W 75 mixed sintered. A thorough process parametric study is carried out involving analysis of the influence particle size distribution, sintering pressure, discharge energy on maximum current obtained residual porosity. Thermal exp...

To assess the exposure of welders to thorium-232 (232Th) during tungsten inert gas arc (TIG) welding, airborne concentrations of 232Th in the breathing zone of the welder and background levels were measured. The radioactive concentrations were 1.11 x 10(-2) Bq/m3 during TIG welding of aluminum (TIG/Al), 1.78 x 10(-4) Bq/m3 during TIG welding of stainless steel (TIG/SS), and 1.93 x 10(-1) Bq/m3 ...

In this paper X-ray microtomography on Plasma Sprayed Tungsten (PS-W) deposited on ferritic-martensitic steel is presented and discussed. PS-W is a challenging material for microtomography since it exhibits a random porous network at different length-scales and it is hardly penetrable by X-rays. Results are presented by application of monochromatic synchrotron light at beamline ID-19 of the ESR...

Measurement of the effects of helium (from tritium decay) on the weldability of Types 304 and ITER Grade 316LN stainless steel demonstrated the inherent complexities in designing and conducting an experimental program using tritium-charged-and-aged materials to simulate the effects of irradiation-induced helium on weld behavior. Differences in microstructure, surface condition and alloy chemist...

A coupled thermal-microstructural simulation model was developed to estimate the thermal history in a eutectoid steel wire rod under continuous cooling and forced-convection. The phenomena of heat transfer, phase transformation estimation boundary condition. histories were analyzed at different rates emulate forced-convection conditions by air-jet as controlled conveyor. acquired used calculate...

V-Si-B and Mo-Si-B alloys are currently the focus of materials research due to their excellent high temperature capabilities. To optimize the mechanical alloying (MA) process for these materials, we compare microstructures, morphology and particles size as well as hardness evolution during the milling process for the model alloys V-9Si-13B and Mo-9Si-8B. A variation of the rotational speed of t...