Fiber having integral weak interface coating, method of making and composite incorporating the fiber
Disclosed is a method of coating a high temperature fiber including depositing a base material on the high temperature fiber using atomic layer deposition, depositing an intermediate material precursor on the base material using molecular layer deposition, depositing a top material on the intermediate material precursor or the intermediate layer using atomic layer deposition, and heat treating the intermediate precursor. The intermediate material in the final coating includes a structural defect, has lower density than the top material or a combination thereof. Also disclosed are the coated high temperature fiber and a composite including the high temperature fiber.
1. A method of coating a high temperature fiber comprising depositing a base material on the high temperature fiber using atomic layer deposition, depositing an intermediate material precursor on the base material by molecular layer deposition, depositing a top material on the intermediate material precursor or intermediate material by atomic layer deposition, and heat treating the intermediate layer precursor to form the intermediate material in contact with the base material, wherein the intermediate layer comprises a structural defect, has a lower density than the top material or a combination thereof.
2. The method of claim 1 , wherein the intermediate material has a structural defect selected from the group consisting of pores, cracks, voids, gaps, dislocations, shear bands and combinations thereof.
3. The method of claim 1 , wherein the intermediate material has a thickness of 0.02 to 50 nm; and
wherein the top material has a porosity that is less than 1% by volume.
4. The method of claim 1 , wherein the intermediate material precursor comprises a hybrid organic/inorganic material.
5. The method of claim 1 , wherein the intermediate material precursor comprises an organic material.
6. The method of claim 1 , wherein the intermediate material has a porosity of 1 to 75%.
7. The method of claim 1 , wherein heat treating comprises heating at a temperature greater than 200° C.