US 12,145,890 B2
Coated (core-shell) nanoparticles for nanocomposite optical ceramics
Richard Wesley Jackson, III, Mystic, CT (US); Kenneth D. Smith, East Longmeadow, MA (US); Ying She, Rocky Hill, CT (US); Stephanie Silberstein Bell, North Andover, MA (US); and Richard Gentilman, Acton, MA (US)
Assigned to RAYTHEON COMPANY, Tewksbury, MA (US)
Filed by Raytheon Company, Waltham, MA (US)
Filed on Dec. 16, 2022, as Appl. No. 18/083,204.
Prior Publication US 2024/0199497 A1, Jun. 20, 2024
Int. Cl. C04B 35/628 (2006.01); C04B 35/10 (2006.01); C04B 35/48 (2006.01); C04B 35/547 (2006.01); C04B 35/581 (2006.01); B82Y 40/00 (2011.01)
CPC C04B 35/62823 (2013.01) [C04B 35/10 (2013.01); C04B 35/48 (2013.01); C04B 35/547 (2013.01); C04B 35/581 (2013.01); C04B 35/62836 (2013.01); C04B 35/62884 (2013.01); B82Y 40/00 (2013.01); C04B 2235/5454 (2013.01); C04B 2235/781 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A nanocomposite optical ceramic (NCOC) material comprising:
a plurality of coated nanoparticles comprising nanoparticles of a first material coated with a coating of a second material, wherein:
the first material and the second material are mutually insoluble;
the first material and the second material each have a transmissivity of at least 80% for an intended wavelength;
the first material and the second material have a difference in index of refraction of less than 25%;
the first material and the second material have grains with a diameter of less than 1/20th the intended wavelength;
the coating of the second material on the nanoparticles of the first material is up to 50 nm thick; and
the NCOC material contains no more than 0.01% voids per unit volume following dry pressing and compacting, sintering, and hot isostatic pressing;
wherein the first material and the second material are selected to limit NCOC grain growth such that the NCOC exhibits grain growth of no greater than 20% when exposed to a temperature of −1400° C. to 1600° C. for one hour.