【Chief members】

Qiang Feng            Professor at the University of Science and Technology Beijing

Guoqing Zhang     Researcher at the Beijing Institute of Aeronautical Materials, Deputy Chief Engineer

Longfei Li               Associate Research at the University of Science and Technology Beijing

Weiwei Zheng       Associate Research at the University of Science and Technology Beijing

【Research Background】

As an irreplaceable core material for the hot-end components used in aero engines and ground gas turbines, superalloys are known as the “cornerstone of advanced engines.” These key hot-end components of the next generation of advanced aero engines and heavy-duty gas turbines can serve in harsher environments, whereas neither traditional cobalt-based nor existing nickel-based superalloys can fully satisfy the operating requirements. Therefore, there is an urgent need to develop new high-temperature structural materials with superior comprehensive properties.

【Research Objectives】

Focusing on the major demands of the future aviation and energy fields, the team aims to create high-throughput design, preparation, and characterization approaches for high-performance superalloys, develop methods for the component design and optimization of new superalloys, and promote the design criteria of these materials. In addition, the team plans to establish a preliminary design and integration technology for high-performance superalloys, thereby promoting the engineering application of these materials. Furthermore, based on the service characteristics of the turbine blades of heavy-duty ground gas turbines and shipborne gas turbine engines, the team aims to develop a novel cobalt-based superalloy with an enhanced temperature capacity and superior comprehensive performance, thereby providing technical reserves for next-generation gas turbine systems.

【Main Research Areas】

1. Development of a high-throughput component design and optimization approach for new superalloys.

2. Development of high-throughput experimental and characterization techniques for advanced superalloys.

3. Clarification regarding the multi-component interaction mechanism of an advanced single-crystal superalloy and its coating.

4. Development of a method to evaluate the service damage of superalloy turbine blades and predict their service life.

【Significant Research Progress】

1. High-throughput component design of a new cobalt-based single-crystal superalloy

The γ' phase-enhanced cobalt-based superalloy is considered a member of the next-generation of high-temperature structural materials with potential applications in the aviation and energy industries. However, the existing γ' phase-enhanced cobalt-based superalloys have problems such as limited basic data and an inadequate temperature capacity and comprehensive performance. To resolve these issues, following the concept of materials genome engineering, our team has conducted research on the component design of a new cobalt-based single-crystal superalloy based on integrated computational materials engineering (ICME). Subsequently, through international cooperation, the team has further established a complex multi-component-diffusion multi-element technology and an experimental high-throughput component-structure characterization technology, systematically investigating the effects of multiple alloying elements including Cr, W, and Mo on the high-temperature phase equilibrium and γ/γ′ stability of the new cobalt-based superalloy, and efficiently identifying the quantitative correspondence among the alloy composition, phase composition, and phase content. Not only have these achievements provided considerable experimental data for improvement of the thermodynamic database of new cobalt-based superalloys, a multi-component single-crystal alloy with the highest γ/γ' structure stability has been created. The performance test results have indicated that this single-crystal alloy exhibits a good high-temperature oxidation resistance and high-temperature creep performance, thereby laying a solid foundation for the research and development of high performance γ' phase-enhanced cobalt-based single-crystal superalloys suitable for engineering applications.

2. Development of an ICME-based method to evaluate the service damage of aero engine turbine blades and predict their service life

The turbine blades of aero engines bear high-temperature and complex stresses during service, which can lead to failures owing to degradations in the microstructure and mechanical performance. To satisfy the urgent need for the reliable safety assessment of aero engine turbine blades, our team has developed a high-throughput characterization technology, and conducted research on the microstructural evolution and structural performance correlation of superalloys used in turbine blades, from which a microstructural evolution characteristic database has been constructed. On this basis, utilizing data mining and machine learning technologies, the team has built a creep-life prediction model for superalloys based on the evolution pattern of the microstructure, and developed a method to predict the service life of turbine blades used in aero engines. This method can accurately evaluate and predict the structural performance correlation under complex working conditions, providing strong technical support for an evaluation of the service reliability and safety of aero engine turbine blades.

Diagram of artificial neural network model for creep-life prediction based on microstructural evolution.