PVD Coatings Extend Life of IGT and Steam Turbine Components


Newly developed PVD coatings provide superior erosion and corrosion protection for high-value turbine components

Industrial Gas Turbine (IGT) manufacturers and MROs are continually seeking new ways to improve the performance and longevity of critical components.  To achieve this, high-value components must be designed and manufactured to withstand increasingly extreme temperatures, particle erosion and hot gas corrosion stress.

Given the critical role of IGTs to utilities and bulk users of power, improving efficiency and extending operating life of critical components is the key to managing costs while maximizing efficiency and uptime. Even seemingly minor factors such as the surface finish of compressor blades, for example, play a key role in increasing fuel efficiency.

As a result, OEMs and MROs are turning to advanced coatings that modify the surface of turbine components to improve wear and corrosion resistance, while also providing a lower coefficient of friction required for metal-on-metal contact of rotating parts such as shafts. One solution in this category that is garnering attention are physical vapor deposition (PVD) coatings for both IGT and steam turbine components.

One REACH compliant PVD coating, BALINIT Turbine Pro from Oerlikon Balzers, is specifically geared towards protecting engine compressor blades, vanes and integrated bladed rotors (blisks) from particle erosion by maintaining a highly polished surface finish to retain efficiency gains for the lifetime of the part.

The formulation delivers a metal aluminum nitride (MeAIN) structure that results in an optimal relation of high hardness to residual compressive stress even under high thermal conditions.  The PVD coating can be applied to steels, super alloys and titanium components and has an extremely low surface roughness once applied.

The high hardness of BALINIT Turbine Pro has already been proven in solid particle, liquid droplet, liquid cavitation, waterjet and other erosion tests with the coating on various substrates (steel, Inconel and titanium) in different coating thickness and high temperatures.

In the solid particle erosion test in which materials were evaluated based on mass loss, for example, BALINIT Turbine Pro demonstrated more than five times higher erosion protection than other PVD coatings, including titanium nitride (TiN).  That value increased to more than 40X when compared to uncoated titanium and even more for steel.

For more information about PVD coating solutions for gas and steam turbines from Oerlikon Balzers, visit www.oerlikon.com/balzers