Aerospace suppliers revisit older turbine coatings as rare-earth supplies tighten.

Rare-earth shortages are prompting aerospace suppliers to reassess turbine-coating materials that fell out of favour decades ago. The National Research Council of Canada and industry partners are evaluating zirconium dioxide and other non-rare-earth ceramic oxides used in the 1970s and 1980s for modern hot-section applications.

European producer Oerlikon Metco said it already sells some rare-earth-free coatings and is developing more, while US suppliers are testing alternatives for less critical components and recycling surplus material. Industry experts cautioned that these steps can ease, but not quickly eliminate, dependence on China.