Influence of Plasma Dynamics on Material Synthesis Product of IPD Process

Abstract

In the present work we discuss recent studies concerning plasma dynamics influence on the material synthesis product of the impulse plasma deposition process. Conditions favourable for evaluation of the Rayleigh-Taylor instability on the current sheet surface were found during the computational studies of plasma movement in the coaxial accelerator. Appearance of this phenomenon explains non-uniform phase composition and morphology of coatings. By modifying the design of the plasma accelerator, we succeeded in reducing substantially Rayleigh-Taylor instability and in obtaining -Al2O3 a coatings instead of common γ -Al2 O3.

Physical Phenomena in Z-pinch Plasma of Impulse Plasma Deposition Process

“…Ea ch oscil l ati on has a wa velength of ab out 0.1À 0 : 5 ñ s, the mean di sta nce between pul sesequa ls 2.0À 2 : 5 ñ s whi l e the dura ti on of o scill ati on p eri od reaches about 2 0 ñ s. The situa ti on rep eats duri ng the second ha lf -p eri od after the change of electro de system pol ari zati on. The observed ti m i ng stri ctl y correl ates wi th sta ges of IPD accelera to r di scharg e predi cted by the theo reti cal m odel [2,3] previ ously worked o ut and wi th pl asma i mages fro m the hi gh-speed fra m e cam era.…”

“…In our earl i er studi es [2] we worked out a physi cal m odel of dyna mi c pheno mena duri ng a coaxi al pha se of IPD di scharg e. There has b een al so, ho wever, a conti nual l y gro wi ng dem and for val i datio n of pl asma dyna m ics code by com pari son wi th rel evant exp eri menta l observ ati ons. Theref ore, a special pro gra m me was sta rted [3,4] to i nvesti gate pl asma dyna m i cs wi th the hel p of hi gh-speed pho to gra phy, X-ra y and i on b eam di agno sti cs.…”