A new ultra-rapid process of flash spark plasma sintering is developed. The idea of flash spark plasma sintering (or flash hot pressing - FHP) stems from the conducted theoretical analysis of the role of thermal runaway phenomena for material processing by flash sintering. The major purpose of the present study is to theoretically analyze the thermal runaway nature of flash sintering and to exp...

Protrusions on the surfaces of electrodes used in high voltage spark gaps lead to local field enhancements, which lower the self-breakdown voltage of the spark gap. Stainless steel, brass, and copper-tungsten electrodes have been tested in a 5-30 kV, 4-25 kA, .1.6 Caul/shot, unipolar, pulsed spark gap with N2 gas or air. The heights and bases of variously shaped protrusions on the surfaces of t...

The aim of the work is to study influence length spark gap on energy input into discharge channel during its gas-dynamic expansion. Methodology. research carried out by numerical modeling process development at variable values and invariable other conditions. was set in range from 1 mm 20 mm. conducted using a model development, which takes account processes nonstationary expansion channel, tra...

A spark gap at pressures from 100 kPa to 7 MPa with various gases is fired by overvolting the electodes. The recovery of the gap is studied using a second identical pulse to test the voltage holdoff during the recovery period. A TV camera, interferometer and a spinning mirror camera are also used to record arc locations and density profiles. The gas is stationary during the recovery. Breakdown ...

The erosion rates for hemispherical electrodes, 2.5 em in diameter, made of graphite, copper-graphite, brass, two types of copper-tungsten, and three types of stainless steel have been examined in a spark gap filled with air or nitrogen at one atmosphere. The electrodes were subjected to 50,000 unipolar pulses (25 )ls, 4-25 kA, 5-30 kV, 0.1-0.6 Coul/shot) at repetition rates ranging from 0.5 to...

We report calculations of the electronic structure of silicene and the stability of its weakly buckled honeycomb lattice in an external electric field oriented perpendicular to the monolayer of Si atoms. The electric field produces a tunable band gap in the Dirac-type electronic spectrum, the gap being suppressed by a factor of about eight by the high polarizability of the system. At low electr...