Plasma supersonic surface strengthening of the parts

Plasma supersonic surface strengthening of the wheel pair flanges of the railway transport improves contact-fatigue resistance of metal and, as a result, raises their resource and reliability. Wear rate of flanges is reduced in 2,5-3 times, crack resistance is improved on 40%, horizontal wear become slower due to the reduction of friction coefficient on 30%.

The technology has two differential characteristic:

— local (in the zone of maximum wearing) strengthening of wheel flange 2,5 — 3 mm deep and 35 mm in width, up to hardness 480 HB;

— changing of the structure with ferrite-pearlite mixture on fine-needled martensite with rosette-like troostite.

Microstructure of wheel with plasma-strengthened layer in the wheel-rolling area of the railway transport : а — slow etching strip, b— cold hardening structure, х 500.

Alternation of the microhardness values on metal depth in the wheel flange rolling area after surface plasma strengthening.

The given technology is realized using special installation PLAZER 50N-2M. High-performance hardening process of flanges (15 minutes for one wheel) provides increasing of wheel pair operating time in 3 times, as well as its reliability, improvement the condition of contact with the rail and can be implemented in the conditions of standard depot. The guaranteed best quality indicators are provided.

Semiautomatic machines for hardening of wheels with rolling out

The process of plasma hardening of wheels without rolling out