I’ve been trying to make sense of what is actually arcing to what, but the September report doesn’t seem to provide the detail.
Can we see a schematic section, with the locations of where the spark occurs and the electrical potential of the surrounding parts? Also, it would be good if you can overlay onto that the lines of magnetic field you expect during the pulse. I say that, because I have a magnetic trap experiment and above a critical voltage I actually get ‘arcs’ between parts of the outer magnetic yoke that are at the same potential. I say they are, because they are electrically connected and I am not even exceeding ‘mA’, let alone ‘MA’!!!
It seems to me that if you have a strong enough convex magnetic field at a point where the (crossed-field) electric fields meet some breakdown criterion, then what will happen is that electrons can become trapped, irrespective of the currents or voltages at the ends of the arc itself. These trapped electrons then cause further ionisation. The ions escape (due to their bigger gyro radius) whilst this apparent ‘arc’ is struck and sustained indefinitely yet seemingly without an actual electrical discharge driving it.
This then becomes self-sustaining, because the excited electrons flow down the magnetic field line, intersect whatever it intersects with, and causes sputtering that then sustains the crossed-field convex magnetic effect.
It’s just a suggestion; the solution, or in-fact the issue, may be to re-design the magnetics of the locality. It may not be the electrical properties of the steel plate that are the issue, but its magnetic behaviour. (Whether Austenitic or not, it will contain some degree of Martensitic content.)
In regards plating, to achieve maximum conductivity I expect you will need to layer your plating, such as a tin layer first, then gold flash over nickel on top of this. If we’re talking low volts and high current, then migration through the layers should be insignificant. I can ask a specialist metallurgist friend what the best recommendation is, if you are sure it is gold you want to end up with on the top. What is the exact grade of stainless? (PM me, if it is proprietary information.)
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