Aerospace Revives 1970s Ceramic Coatings Amid China Rare-Earth Squeeze
Jet engine manufacturers are retesting legacy zirconia materials to replace rare-earth thermal barrier coatings as Chinese supply constraints tighten.
Key points
- Aerospace firms are retesting 1970s-era zirconium dioxide coatings to replace rare-earth materials due to Chinese supply disruptions.
- Oerlikon Metco is selling non-rare-earth thermal barrier coatings using magnesium and calcium oxides to mitigate supply risks.
- Industry experts estimate that reducing reliance on Chinese rare earths will take years, not months, despite immediate material substitutions.
The aerospace sector is re-evaluating thermal barrier coating materials from the 1970s and 1980s in response to a disruption in Chinese rare-earth supplies. According to Chosunbiz, rising procurement risks and price pressures stemming from U.S.-China tensions have forced industry partners to seek alternatives to current yttrium-based systems.
The National Research Council of Canada and industry allies are currently testing zirconium dioxide and other ceramic oxides that do not rely on rare earths. These legacy materials, sidelined for five decades by newer rare-earth compounds, are being revisited to protect jet engine components from extreme temperatures without exposing supply chains to geopolitical vulnerability.
Legacy materials return to production lines
European firm Oerlikon Metco has begun selling non-rare-earth products, including zirconia-based coatings utilizing magnesium and calcium oxides. This technology predates the rare-earth-reinforced materials now standard in the industry. The move reflects a broader shift as suppliers seek to insulate production from the volatility of critical mineral markets dominated by China.
U.S. suppliers are also reviewing non-rare-earth substitutes for lower-priority engine parts. Additionally, discussions have emerged regarding the recycling of leftover coating materials to alleviate supply shortages. These operational adjustments aim to maintain output stability while permanent supply chain diversification efforts take shape.
Technical improvements enable older material performance
Rogério Lima, a senior researcher at the NRC, stated that modern measurement equipment and engineering capabilities allow for the performance enhancement of these older materials. The research focuses on integrating contemporary processing techniques with legacy chemical compositions. This approach attempts to close the performance gap that previously favored rare-earth-based coatings.
Dependence on Chinese supply persists for years
Experts warn that breaking dependence on Chinese rare earths will take years rather than months. Jeffrey Gertz of the Center for a New American Security noted that securing replacement technology or sufficient domestic supply requires significant time. The retesting of 50-year-old materials underscores the depth of the current supply chain vulnerability.
