Surface Modificationof 316L Stainless Steel with Plasma Sprayed Coatings of Al-Cu Alloy

The SiO₂ films were deposited on SrAl₂O₄ grains via bottom-up chemical route.The SrAl₂O₄-doped Al-Cu and SiO₂/SrAl₂O₄-doped alloy coatings were synthesized by plasma spraying of a mixture of Al-Cu alloy powder SrAl₂O₄ or Si-coated SrAl₂O₄ dopant powders,respectively,on substrate of 316 L stainless steel,a construction material.The influence of the dopants,including SrAl₂O₄ and SiO₂-covered SrAl₂O₄ on the tribological properties and interfacial adhesion was investigated with SEM and conventional mechanical probes.The results show that the three types of the Al-Cu coatings all had a major impact on surface modification.When it comes to hardness,wear-resistance and interfacial adhesion,a descending order appeared:SiO₂/SrAl₂O₄-doped Al-Cu >SrAl₂O₄-doped Al-Cu >Al-Cu >316 L;when it comes to dynamic friction coefficient,an ascending order showed up.Possible mechanisms responsible for the improved tribological behavior were tentatively discussed in a thought provoking way.