Fraunhofer Institute for Mechanics of Materials IWMAs the most important industrial material, steel comes in more than 2,500 varieties that are highly specialized for different applications. Even the smallest changes in composition can alter the material structure on an atomic scale and improve the material behavior “on a large scale.” The consortium of the EU project Z-Ultra, led by Fraunhofer IWM, developed new 12% chromium steels for high-temperature applications that are up to 30% stronger than conventional 9% chromium steels and can withstand higher temperatures and pressures for longer periods of time in power plants. Atomistic simulation methods supported the steel developers in developing the alloys in a targeted manner.
Z phase strengthened steels for ultra-supercritical power plants
Completed research project
Project description
The Z-Ultra project focused on developing Z-phase-reinforced steels for use in ultra-supercritical steam power plants. These power plants require materials with excellent creep resistance and oxidation resistance at temperatures above 650°C in order to increase efficiency and reduce CO₂ emissions.
The aim of the project was to develop new martensitic 12%Cr steels that are stabilized by targeted nanoscale Z-phase precipitates and thus exhibit long-term high-temperature resistance.
Fraunhofer IWM subproject:
Materials modeling, simulation, and experimental characterization of the developed Z-phase-reinforced steels.
- Development of models for predicting Z-phase formation, creep resistance, and mechanical properties
- Investigation of microstructure, oxidation, corrosion, and thermomechanical properties
- Optimization of heat treatments, welding processes, and service life predictions
- Support for the integration of new steels in power plant environments
Transfer of project results to the following Fraunhofer IWM R&D services for companies:
- Design and optimization of high-temperature-resistant steels with improved creep resistance and oxidation resistance
- Service life predictions and materials simulations to design components more efficiently
- Validation of heat treatment and welding processes for high-performance materials
- Materials testing and integration of new alloys in power plants and high-performance facilities
