Fe2+: MgF2 laser ceramics via Co-precipitation with 90% Mid-IR transparency and enhanced thermal conductivity

Polycrystalline MgF 2 is an attractive mid-infrared laser host material, yet its widespread application in high-power systems is limited by its inferior thermal conductivity compared to single-crystal materials, resulting in inefficient heat dissipation. To address this challenge, we successfully designed and synthesized Fe 2+ : MgF 2 transparent ceramics using a strategic wet chemical coprecipitation method combined with hot-press sintering. This method enables precise Fe 2+ doping within the MgF 2 lattice (Fe x Mg 1-x F 2 , 0.0002≤x ≤ 0.05), with doping effects clearly confirmed by XRD, XPS, and TEM analyses. The resulting ceramics exhibit outstanding mid-infrared transmission properties, with 1-mm-thick samples achieving 90% linear transmittance at 5.7 μm wavelength. More importantly, Fe 2+ incorporation significantly enhances thermal conductivity—peaking at 20.3 W/(m·K), a substantial increase over the baseline value of 11.6 W/(m·K)—while simultaneously raising Vickers hardness to 5.49 ± 0.54 GPa, fulfilling the core design objective. This simultaneous achievement of high optical quality and exceptional thermal management demonstrates that Fe 2+ : MgF 2 transparent ceramics represent a highly promising and reliable candidate material for high-power mid-infrared laser applications.