Magnetron Sputtered NbN Films with Nb Interlayer

TL;DR

This study investigates the deposition of NbN films with an Nb interlayer on stainless steel substrates using magnetron sputtering, optimizing process parameters and evaluating surface hardness and corrosion resistance improvements.

Contribution

It introduces a duplex coating process with an Nb interlayer to enhance surface hardness and corrosion resistance of NbN films on steel substrates.

Findings

Optimized N2 flow rate and substrate biasing for NbN deposition.

Interlayer improves surface hardness and corrosion resistance.

Duplex coatings show enhanced performance over single-layer films.

Abstract

NbN films were deposited on SS substrates by reactive DC magnetron sputtering at various N2 flow rates and substrate biasing. Effect of N2 flow rate and substrate biasing has been studied on deposition rate, surface hardness, crystal-structure and adhesion values. Process parameters were optimized for deposition of NbN coatings. NbN coatings were then deposited on to MS substrates as such and with Nb interlayer deposited by magnetron sputtering. The thickness of interlayer was 2 \mum. The duplex coating has been studied for the improvement with respect to surface hardness by Knoop micro indentation and corrosion performance by potentiodynamic polarization technique. Open circuit potentials were also measured.