Effect of Temperature Ramp Rate on the Morphology, Phase and Adhesion Strength of Ag-Ta2O5 Thin Film

Abstract

The short life of coatings layered on a SS 316L substrate can cause severe problems resulting from the weak crystallization of the film phase and low adhesion strength of the coating on the substrate. In this work, reactive magnetron sputtering is utilized to fabricate durable Ag/Ta2O5 nanocomposite coatings for surgical tool applications. A 5.74-µm-thick Ag/Ta2O5 nanocomposite coating was deposited on the SS 316L substrate. The homogeneously distributed as-deposited nanoparticles increased the total surface area for antibacterial activity. Post-thermal treatment at 500°C was conducted at temperature ramp rates of 2°C/min and 5°C/min. Microstructural, elemental, phase, structure and adhesion strength analyses were performed to characterize the deposited films. A larger amount of segregated Ag particles per area was achieved at a temperature ramp rate of 2°C/min, which led to comparably higher adhesion strength. The adhesion strength of the film annealed at 2°C/min improved by 271% compared to the as-deposited film.