To keep prices of serial manufactured new parts at the lowest possible level without any loss of quality it is feasible to produce the part out of a more reasonable priced material which is also adapted to the mechanical demands. The strained areas will be later covered with a thermal sprayed layer.
The pictured example shows a CNC-produced water pump shaft made of stainless steel 1.4462. Its seal seat was coated with a layer of 1.4034. The coat was applied with High Velocity Oxygen Fuel flame spraying (HVOF) and therefore it has a porosity of under 2 %.
Coats of different materials until high-strength ceramic or hard metals (carbides) can be applied according to customers requirements without any problems.