摘要:
The present invention is generally directed to methods of making ceramics with nanoscale/microscale structure involving self-assembly of precursor materials such as, but not limited to, inorganic-based block co-polymers, inorganic-/organic-based hybrid block co-polymers, and other similar materials, and to the structures made by such methods. Where such precursor materials are themselves novel, the present invention is also generally directed to those materials and their synthesis.
摘要:
The disclosure provides for an article (10) including a substrate (12), an environmental barrier coating (EBC) (16), a bondcoat (14), and a boron source (20). The substrate (12) includes a silicon-including material. The EBC (16) is disposed over the substrate (12), and the bondcoat (14) is disposed between the substrate (12) and the EBC (16). The bondcoat (14) includes silicon. The boron source (20) is disposed within the article (10) to provide an effective amount of boron to form an oxide (18) including silicon and at least 0.1 weight percent boron during exposure of the bondcoat (14) to an oxidizing environment at a temperature greater than 900 degrees Celsius. The oxide (18) may be a borosilicate glass that is substantially devitrification resistant to prevent spallation of the EBC (16) and thereby enhance the temperature capability of the article (10).
摘要:
A method of forming a nanoscale ceramic composite (100) generally includes modifying a polymeric ceramic precursor, mixing the modified polymeric ceramic precursor with a block copolymer to form a mixture, forming an ordered structure from the mixture, wherein the modified polymeric ceramic precursor selectively associates with a specific type of block of the block copolymer, and heating the ordered structure for a time and at a temperature effective to form the nanoscale ceramic composite (100). Also claimed are the nanoscale composite formed by the method, a polycarbosilane and a method of modifying a polycarbosilane.
摘要:
A method of forming a nanoscale ceramic composite (100) generally includes modifying a polymeric ceramic precursor, mixing the modified polymeric ceramic precursor with a block copolymer to form a mixture, forming an ordered structure from the mixture, wherein the modified polymeric ceramic precursor selectively associates with a specific type of block of the block copolymer, and heating the ordered structure for a time and at a temperature effective to form the nanoscale ceramic composite (100).