Oxidation resistance of laser cladding by Ni-Cr-Al alloys on carbon and austenitic stainless steel

摘要

A study was made of surface cladding using a 5 kW CO2 continuous wave laser. A powder spraying technique was used for Ni‐Cr‐Al cladding of mild and type 316 stainless steels. Following the process, the microstructure of samples obtained was analysed and these were subsequently tested in an oxidising environment at 950 °C, observing microstructure development, oxide layer formation and process kinetics. A general conclusion to be drawn is, regardless of the base metal on which coatings are formed, that the alloys are highly resistant to oxidation, which is surely due to the formation of protective alumina layers against oxidant attack.