Katoda ignitor determination of the eroded mass for various ignitor cathode materials

DETERMINATION OF THE ERODED MASS FOR VARIOUS IGNITOR CATHODE MATERIALS. Ignitor electrode system has a function of initiating plasma discharge, it consists of two ignitor electrodes complete with one unit of ignitor discharge power supply with 2 flyback transformer, flyback ferrite core of 1,3 cm and 1,5 cm respectively in diameter, futhermore it can be obtained different plasma currents spot for both ignitor electrode systems. Plasma spot current depends on the type of cathode material. The greater of current flows toward the cathode, the greater of plasma spot is generated, so that the eroded cathode material is getting greater too. In this study, the function test of ignitor electrode system has been conducted, from the results of function test can be determined the mass and the particle size of the ignitor cathode material eroded, and can be correlated to lifetime of cathode due to the loss of material at the surface of the cathode after forming plasma spot. The test results of plasma spot on the surface of ignitor cathode using the Ag, Al, Cd and Cu materials, respectively are obtained from plasma spot currents of 14,32 A, 12,34 A, 12,56 A and 10,58 A and the pulse width of 22 μs, 39 μs, 38 μs and 34 μs. The good cathode material for the ignitor electrode system is magnesium and aluminium because they have the low erosion rate γ (11.7 μg/C and 14 μg/C), furthermore they are not easily eroded and damaged. From the results of function test of plasma spot obtained the lowest eroded cathode mass is Al i.e. 6.74 nano grams and the cathode will be reduced along 88.26 μm, while the highest of eroded cathode mass is Cd (erosion rate of 43.9 μg/C) of 20.95 nanograms, the cathode will decrease along 85.67 μm.