High-Entropy Rare Earth Zirconate Thermal Barrier Coatings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Yttria-stabilized zirconia (YSZ) heat shield coatings deteriorate at high temperatures due to sintering density limitations and phase changes above 1200°C, leading to reduced thermal durability and low heat conversion efficiency.
Innovation Solution
A high-entropy rare earth zirconate material with a defective fluorite or pyrochlore structure, represented by A2Zr2O7, is developed, incorporating multiple trivalent and divalent cations to maintain a stable single phase up to 1200°C, with increased lattice distortion and oxygen vacancies to suppress heat transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If YSZ is used as heat shield coating material, then excellent thermal properties and mechanical strength are achieved, but thermal durability deteriorates due to phase change above 1200°C
Solution Approach 1:
The invention changes the compositional parameters by incorporating multiple rare earth elements (La, Nd, Sm, Gd, Dy, Er, Yb) in specific ratios along with zirconia, creating a high-entropy composite material that maintains cubic phase stability up to 1200°C while retaining mechanical strength. This compositional parameter change prevents the tetragonal-to-monoclinic phase transition that causes YSZ degradation.
Solution Approach 2:
The invention uses a composite material system combining multiple rare earth oxides (La2O3, Nd2O3, Sm2O3, Gd2O3, Dy2O3, Er2O3, Yb2O3) with ZrO2 in a high-entropy configuration. This composite structure creates lattice distortion and stabilizes the cubic phase, preventing harmful phase transitions while maintaining the desired mechanical and thermal properties.
2Object-affected harmful factors
If YSZ is used for heat shielding, then good heat barrier effect is achieved, but heat conversion efficiency is low due to high thermal conductivity
Solution Approach 1:
The invention optimizes thermal conductivity parameters by incorporating rare earth elements with different ionic radii and electronic configurations. The high-entropy composite structure creates phonon scattering centers that reduce thermal conductivity from 3 W/mK (YSZ) to below 2 W/mK, improving heat conversion efficiency while maintaining adequate heat barrier protection.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The high-entropy rare earth zirconate exhibits enhanced heat barrier effects and maintains structural stability without phase change, achieving low thermal conductivity and improved thermophysical properties, suitable for high-temperature applications such as aircraft and gas turbine engines.
Implementation Method 1
the structure of the high-entropy rare earth zirconate of the present invention has increased lattice distortion and oxygen vacancies compared to the conventional rare earth zirconate, thereby suppressing heat transfer
Implementation Method 2
it can exhibit an excellent heat barrier effect and can maintain a stable single phase without phase change even in a high temperature environment of 1000° C. or higher
Data Source
AI summary
The present invention relates to high-entropy rare earth zirconates. The high-entropy rare earth zirconate structure of the present invention has a single phase, and, compared to the conventional rare earth zirconate, lattice distortion increases and oxygen vacancies are increased to suppress heat transfer, so it can be confirmed that it has an excellent heat barrier effect as a heat shield coating material. It can maintain a stable single phase without phase change even in a high temperature environment of 1000°° C. or higher.