Northrop Grumman has been granted a patent for a preceramic resin formulation that includes a polycarbosilane preceramic polymer, an organically modified silicon dioxide preceramic polymer, and optional fillers. The formulation is designed to have a specific viscosity and can be used to impregnate fibers, creating a composite material. The impregnated fibers consist of a mixture of fibers and the preceramic resin formulation, which includes fillers of different particle sizes. The patent also covers methods of forming a ceramic matrix composite. GlobalData’s report on Northrop Grumman gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on Northrop Grumman, superconducting quantum circuits was a key innovation area identified from patents. Northrop Grumman's grant share as of September 2023 was 66%. Grant share is based on the ratio of number of grants to total number of patents.
Patent granted for preceramic resin formulation for impregnated fibers
A recently granted patent (Publication Number: US11773029B2) describes impregnated fibers and composite materials made from a preceramic resin formulation. The impregnated fibers consist of fibers combined with a preceramic resin formulation that includes a polycarbosilane preceramic polymer, an organically modified silicon dioxide preceramic polymer, and at least one filler. The filler is composed of two types of particles, with the first particles having a mean diameter of less than about 1.0 µm and the second particles having a mean diameter ranging from about 1.5 µm to about 5 µm.
The patent also covers a composite material made from the impregnated fibers and a reaction product of the polycarbosilane preceramic polymer, the organically modified silicon dioxide preceramic polymer, and the filler. This composite material can be used in various applications, including rocket motor nozzles, rocket motor casings, turbines, turbine blades, turbine housings, turbine engine vanes, insulating tiles, rotor blades, insulation blankets, compressor blades, wing components, fuselage skins, landing gears, exhaust nozzles, engine exhaust ducts, nose cones, re-entry shields, and heat shields.
Furthermore, the patent describes a method for forming a ceramic matrix composite using the impregnated fibers. The method involves passing fibers through a preceramic resin formulation containing the polycarbosilane preceramic polymer and the organically modified silicon dioxide preceramic polymer. The fibers can be polyacrylonitrile-based or pitch-based, and they are impregnated with the preceramic resin formulation to form continuous fibers. The impregnated fibers are then formed into a composite material, either at a net shape or a near-net shape, and cured at a temperature of about 121°C to about 371°C. The composite material is then ceramified at a temperature greater than about 816°C.
The method also includes the option of adding zirconium dioxide or titanium diboride to the preceramic resin formulation, and the impregnated fibers can be cured and ceramified in a single heat treatment at a temperature of about 1,200°C. The resulting composite material exhibits a ceramic yield of greater than about 90% and a mass loss of less than about 10%. Additionally, the composite material can be machined after formation.
Overall, this patent provides a novel approach to creating impregnated fibers and composite materials with specific properties, offering potential applications in various high-temperature environments such as aerospace and industrial settings.