Impact of Laser Power on Erosion Resistance of 304L Stainless Steel Surface Modified with Laser Cladded Fe-Cr Coatings

The surfaces of 304 L stainless steel were modified with the Fe-Cr coatings synthesized by laser cladding.The influence of the laser power on the microstructures and erosion behavior of Fe-Cr coatings was investigated with X-ray diffraction,scanning electron microscopy and sandblasting test.The results show that the laser power had a major impact.For instance,as the laser power increased from 0.5 to 4.0 kW,the wear-resistance/compactness/density of the amorphous Fe-Cr coating with reduced porosity increased,the surface hardness(lower than that of the substrate)decreased with a linearly-decreasing hardness depth profile,accompanied by an increasing interfacial adhesion because the rapid alloying/crystallization/solidification occurred at the interface of cladded Fe-Cr layer and 304 L stainless steel.Small pits and cracks were created on the cladded Fe-Cr coatings by the sandblasting at a large impinging angle.