Technical Expertise

PVD, CVD and plasma-assisted coating processes

I have worked with hard, wear-resistant, erosion-resistant, antifriction and functional coatings produced by PVD, cathodic arc, magnetron sputtering, CVD and PECVD routes.

The useful question is rarely just “which coating?”. It is usually a combination of substrate state, interface preparation, source configuration, ion energy, temperature, residual stress, coating thickness and the way the part will actually fail in service.

For complex geometry or internal surfaces I pay particular attention to transport and access: whether activated species and ions can actually reach the surface that is expected to be modified.

Plasma nitriding and vacuum thermochemical treatment

Precision plasma nitriding, LPC and duplex routes are important parts of my work because they sit exactly at the boundary between metallurgy and equipment control.

For nitriding I look at temperature, plasma condition, gas composition, compound-layer formation, diffusion depth, dimensional change and the geometry of holes or shielded surfaces. For LPC the discussion shifts to boost-diffusion timing, carbon profile, case depth, quenching and distortion.

I do not treat LPC as automatically “better” than gas carburizing, or plasma nitriding as automatically superior to another route. The replacement has to be checked against the function of the part and the required layer.

Vacuum equipment and acceptance

Ultimate pressure alone is a weak description of a vacuum system. I am usually more interested in how the chamber reaches that pressure, what happens under gas load, how much of the pressure rise comes from leaks versus outgassing, and whether the installed diagnostics can distinguish those effects.

For process equipment the vacuum system cannot be separated from heating, gas delivery, plasma power, fixtures, cooling, interlocks and data recording. A FAT should test the combined system, not only isolated components.

Space vacuum, cathodes and electric-propulsion test systems

High-vacuum test work adds another layer because xenon load, contamination, cryogenic surfaces, diagnostics and cathode behaviour interact with the chamber itself.

For cathodes I am interested in ignition, restart, I-V behaviour, drift, thermal state and post-test inspection. For the chamber, effective pumping speed at the operating gas flow matters more than an unloaded base-pressure number.