Investigation of infrared radiation characteristics of MgO-doped YSZ coatings fabricated via atmospheric plasma spraying

Yttrium-stabilized zirconia (YSZ) plays a vital role in infrared stealth technology, owing to its exceptional thermal stability and electrical conductivity. However, its emissivity in the critical 3–5 μm wavelength range remains relatively high, prompting the need for further reductions as aircraft operational temperatures increase. This study investigates the preparation of YSZ coatings doped with magnesium oxide (MgO) using atmospheric plasma spraying (APS) and evaluates the effects of varying MgO concentrations on the microstructure, crystal structure, and infrared emissivity of the coatings. The findings indicate that MgO doping significantly enhances the concentration of oxygen vacancies and promotes grain growth, resulting in a marked reduction in emissivity to 0.55 at 5 mol% MgO. Additionally, high-temperature emissivity assessments demonstrate a continued decrease in emissivity with rising temperature, underscoring the potential of MgO-doped YSZ coatings for advanced stealth applications.