Construction of a low-lightness, low-emissivity and color-matched coating system with robust durability for visible-infrared compatible stealth

With the rapid development of detection technologies, including visible (VIS) imaging and infrared (IR) sensing, the detectability of targets in complex environments has been significantly enhanced, driving the urgent demands on coating systems capable of simultaneously achieving VIS and IR stealth. Conventional coatings that use metallic fillers for low IR emissivity often exhibit high lightness ( L* ), impairing visual camouflage. Conversely, incorporating pigments to regulate visual features usually increases IR emissivity, making it challenging to balance both VIS and IR stealth performance. To address this challenge, we developed a bilayer low- L* VIS-IR compatible stealth coating system (C S ) that synergistically combined spectral modulation with thermal management. SiO 2 -coated Al composite fillers (SiO 2 @Al) were employed in the upper layer to reduce L* while maintaining low IR emissivity, and Cr 2 O 3 pigments were introduced for precise chromaticity regulation to achieve effective color matching with a standard forest green background. The lower layer consisted of a silica aerogel (SA) based thermal-insulating coating, which effectively blocks heat transfer, thereby reducing thermal radiation. The resulting C S achieved an IR emissivity below 0.4 across the 8–14 μm spectrum, a low L* of 33.0, and a color difference of 2.1 relative to the target. Moreover, the IR emissivity and ΔE of C S remained nearly unchanged after environmental durability tests and demonstrated excellent adhesion (grade 0), providing a practical and engineering-feasible strategy for VIS-IR compatible stealth.