I think he means HVOF (High Velocity Oxy Fuel) (Jet-Coat).
Not really welding, the particals are propelled at ultra speed all most like explosive welding, No high temp heat is applied to the shaft and will not alter the properties of the shaft material.
It will do the job very well, We use if for very critical applications, difference being we, Jet-Coat the bore of the wheel (maybe not practical in this application) but we do the wheels for reasons not related to material properties.