Granted Patent B2

US 12,540,105 · App. 17/248,760 · Granted Feb 3, 2026

Inventors: Mehrad Mehr (Raleigh, NC); Bahram Jadidian (Watchung, NJ)

Assignee: Honeywell International Inc.

C04B41/522C04B35/83C04B41/009C04B41/4515C04B41/4517C04B41/4543C04B41/4554C04B41/5025C04B41/5057C04B41/87C04B41/89C04B2235/422C04B2235/5248

Abstract

Claims (32)

1 . A method, comprising:

forming a crystallized metal carbide undercoat on a surface of a carbon-carbon composite substrate; and

forming an overcoat on a surface of the crystallized metal carbide undercoat,

wherein the overcoat comprises a plurality of crystallized ultra-high melting point overcoat layers,

wherein at least two overcoat layers of the plurality of overcoat layers have at least one of a different coefficient of thermal expansion, thermal conductivity, porosity, or thermal stability,

wherein each overcoat layer is sequentially formed on an underlying layer by at least:

applying a mixture to a surface of the underlying layer, wherein the mixture comprises a plurality of ultra-high melting point refractory ceramic particles and a pre-ceramic polymer, wherein the ultra-high melting point refractory ceramic particles have a melting point of at least about 2400° C.; and

prior to applying a mixture for a subsequent layer, heating, in an inert atmosphere or under vacuum, the mixture to a heat treatment temperature to pyrolyze the pre-ceramic polymer and form the overcoat layer,

wherein each overcoat layer comprises a crystallized ultra-high melting point polymer-derived ceramic matrix that includes the plurality of ultra-high melting point refractory ceramic particles, and

wherein an outermost layer of the overcoat comprises an outermost overcoat layer of the plurality of overcoat layers.

2 . The method of claim 1 , wherein a melting point of the ultra-high melting point polymer-derived ceramic matrix is greater than about 1500 degrees Celsius (° C.).

3 . The method of claim 1 , wherein at least two layers of the plurality of overcoat layers include a ceramic matrix having at least one of a different coefficient of thermal expansion or a different thermal conductivity.

4 . The method of claim 1 , wherein a melting point of the ceramic matrix of the outermost overcoat layer of the plurality of overcoat layers is higher than a melting point of the ceramic matrix of an underlying overcoat layer of the plurality of overcoat layers.

5 . The method of claim 1 , wherein at least one of:

a first mixture used to form a first layer of the plurality of overcoat layers includes a different average particle size or shape of the plurality of ultra-high melting point refractory ceramic particles than a second mixture used to form a second layer of the plurality of overcoat layers, or

a first mixture used to form a first layer of the plurality of overcoat layers includes a different particle size distribution of the plurality of ultra-high melting point refractory ceramic particles than a second mixture used to form a second layer of the plurality of overcoat layers.

6 . The method of claim 1 , wherein at least one of:

a first mixture used to form a first layer of the plurality of overcoat layers includes a different particle composition of the plurality of ultra-high melting point refractory ceramic particles than a second mixture used to form a second layer of the plurality of overcoat layers,

a first mixture used to form a first layer of the plurality of overcoat layers includes a different mixture of particle compositions of the plurality of ultra-high melting point refractory ceramic particles than a second mixture used to form a second layer of the plurality of overcoat layers, or

a first mixture used to form a first layer of the plurality of overcoat layers includes a different composition of the pre-ceramic polymer than a second mixture used to form a second layer of the plurality of overcoat layers.

7 . The method of claim 1 , a first layer of the plurality of overcoat layers includes a different volume ratio of the ceramic matrix to the plurality of ultra-high melting point refractory ceramic particles compared to a second layer of the plurality of overcoat layers.

8 . The method of claim 7 , wherein each layer of the plurality of overcoat layers includes a varying volume ratio of the ceramic matrix to the plurality of ultra-high melting point refractory ceramic particles from the surface of the crystallized metal carbide undercoat to a surface of the overcoat.

9 . The method of claim 1 , wherein applying the mixture to the surface comprises at least one of brush painting the mixture onto the surface or spray painting the mixture onto the surface.

10 . The method of claim 1 , further comprising:

applying a metal carbide coating to a surface of the plurality of overcoat layers; and

heating the metal carbide coating to form a metal oxide coating.

11 . The method of claim 1 , wherein forming the overcoat on the surface of the crystallized metal carbide undercoat comprises at least:

applying a first mixture to the surface of the crystallized metal carbide undercoat;

heating the first mixture to the heat treatment temperature to pyrolyze a pre-ceramic polymer of the first mixture and form a first overcoat layer;

applying a second mixture, different from the first mixture, to a surface of the first overcoat layer; and

heating the second mixture to the heat treatment temperature to pyrolyze a pre-ceramic polymer of the second mixture and form a second overcoat layer.

12 . The method of claim 1 , wherein the ultra-high melting point refractory ceramic particles include at least one of hafnium carbide (HfC), hafnium nitride (HfN), hafnium diboride (HfB 2 ), tantalum carbide (TaC), tantalum diboride (TB 2 ), silicon carbide (SiC), zirconium diboride and silicon carbide (ZrB 2 —20% SiC), hafnium diboride and silicon carbide (HfB 2 —20% SiC), hafnium oxide (HfO 2 ), tungsten carbide (WC), or rhenium carbide (ReC).

Assignments (1)

Continuity (1)

References Cited (31)