Induction Heating Meets Extreme Conditions: Supporting Advanced Turbine Materials Research

Engineers designing the next generation of power turbines face a difficult question: how do you know if a material will hold up under conditions most equipment was never built to survive?

Researchers at Southwest Research Institute (SwRI) were tackling exactly that problem as part of a U.S. Department of Energy-sponsored project to develop an oxy-combustion turbine capable of generating 150 to 300 megawatts of electricity with near-zero carbon emissions. The turbine's design called for inlet temperatures exceeding 1,100°C and pressures approaching 300 bar, conditions far beyond what conventional turbine materials are typically tested for.

To move the project forward, the SwRI team needed to test candidate alloys and coatings directly in supercritical CO2 at these extreme temperatures and pressures. The problem? Traditional testing methods rely on heating an entire pressure vessel from the outside. At the temperatures required for this project, that approach would have pushed the vessel itself well past its safety rating.

Rather than heating the entire test chamber, the SwRI research team designed a novel approach: place an induction heating coil inside the pressurized autoclave itself, creating a highly localized heat zone around the test specimens while keeping the surrounding vessel at a much lower, safer temperature.

This allowed the team to reach temperatures exceeding 1,000°C in the immediate test zone, while the outer vessel walls stayed below 350°C, well within its pressure rating.

Achieving this required precise integration between the induction heating system and the high-pressure vessel itself, along with careful attention to component placement, cooling, and thermal isolation to protect sensitive parts like seals and fittings from the intense heat generated just inches away.

One of our induction engineers, Ray Ariss, worked closely with the SwRI team to integrate the induction heating system with the autoclave and troubleshoot the setup, helping ensure reliable, sustained performance under extreme conditions.

Using this induction-heated autoclave setup, the SwRI team successfully tested six candidate alloys, including nickel superalloys and stainless steels, both bare and with various protective coatings, over a total of 1,500 hours of exposure to supercritical CO2 at temperatures near 1,000°C and pressures around 250 bar.

The results confirmed that the induction heating approach could reliably replicate the extreme conditions expected inside an oxy-combustion turbine, giving researchers confidence in the materials data they collected. Key findings included:

• Bare nickel alloys showed higher oxidation rates than ferrous alloys under these conditions
• Protective bond coatings significantly reduced oxidation across nearly all tested materials
• Oxidation rates increased sharply as temperatures rose from 800°C to 1,000°C

This project demonstrates a capability that extends well beyond a single power plant application: the ability to create precisely controlled, extremely high-temperature zones inside sealed, high-pressure environments using induction heating. This is a specialized engineering challenge with relevance across industries where equipment must be tested or operated under extreme conditions, including aerospace and energy applications.

This work was conducted by Southwest Research Institute as part of a U.S. Department of Energy-sponsored project (Award Number DE-FE0031929) and was presented at the International Supercritical CO2 Energy Technologies Symposium in March 2026.

Facing a testing challenge in extreme temperature or pressure conditions? Contact Induction Technology Solutions to discuss how induction heating can be adapted to your application.