Research on the microstructure and properties of antimicrobial stainless steel coatings on Q345R alloy steel by electron beam surface coating

Abstract

In this study, 304 antimicrobial stainless steel coatings were prepared by the electron beam melting of antimicrobial stainless steel powder, in an attempt to enhance the surface properties of Q345R steel. Besides, the effect of Cu-containing 304 powder coatings on the microstructure, mechanical properties, and electrochemical properties of the Q345R surface was investigated. The results indicated that the coating grain was refined, the dislocation density was increased, and both the plasticity and toughness were enhanced after the electron beam surface coating (EBSC) treatment. Additionally, the hardness of coatings was also enhanced under the three beam currents due to grain refinement and dislocation strengthening. At a beam current of 28 mA, the coating hardness reached a maximum of 384.078 HV, representing a two-fold increase compared with the base material (BM) hardness of 131.048 HV. Moreover, the abrasion resistance of the coating was superior to that of the BM. At a beam current of 28mA, the wear volume and wear rate were minimized to only 10 % of the wear volume of substrates. In galvanic corrosion measurements, the coatings displayed better corrosion resistance than the substrates, and these samples at a beam current of 28 mA exhibited the best corrosion resistance. Overall, the E-beam surface melting 304 stainless steel coating can effectively improve the properties of Q345R carbon steel.