Abstract:
This research investigates the effect of quenching current, nozzle-tosurface distance, plasma-forming gas flow rate, and rate of cooling on
both plasma torch travel speed (treatment speed) and nozzle diameter.
Cooling rates were calculated for various quenching currents based on
heat transfer theory. Results show that the relative significance of primary
plasma selective quenching parameters remains consistent for both
hardened zone depth and width. Notably, the effect of quenching current
on hardened zone depth significantly exceeds that of other parameters,
highlighting its critical role for optimizing railroad wheel performance.
We propose a novel method for controlling the mechanical properties of
the hardened surface through regulating wheelset rotational speed during
quenching. This approach has the potential to significantly improve the
wear resistance and lifespan of railroad wheels, leading to substantial cost
savings for the railway industry.
