Fiber having integral weak interface coating, method of making and composite incorporating the fiber

Abstract

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.

What is claimed is: 
     
         1 . A coated high temperature fiber comprising a multi-material coating on the high temperature fiber wherein the multi-material coating has a base material in contact with the high temperature fiber, an intermediate material in contact with the base material and a top material in contact with the intermediate material and further wherein the intermediate material comprises a structural defect, has a lower density than the top material or a combination thereof. 
     
     
         2 . The coated high temperature fiber 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 coated high temperature fiber of  claim 1 , wherein the base material has a thickness of 1 to 10,000 nm. 
     
     
         4 . The coated high temperature fiber of  claim 1 , wherein the intermediate material comprises a metal oxide, carbide, nitride, or boride material and combinations thereof. 
     
     
         5 . The coated high temperature fiber of  claim 1 , wherein the intermediate material has a porosity of 1 to 75%. 
     
     
         6 . The coated high temperature fiber of  claim 1 , wherein the intermediate material has a thickness of 0.02 to 50 nm. 
     
     
         7 . The coated high temperature fiber of  claim 1 , wherein the top material has a thickness of 1 to 10,000 nm. 
     
     
         8 . A composite comprising a coated high temperature fiber disposed in a matrix wherein the coated high temperature fiber has a multi-material coating on the high temperature fiber and the multi-material coating has a base material in contact with the high temperature fiber, an intermediate material in contact with the base material and a top material in contact with the intermediate material and further wherein the intermediate material has a structural defect, has lower density than the top material, or a combination thereof. 
     
     
         9 . The composite of  claim 8 , wherein the intermediate material has a structural defect selected from the group consisting of pores, cracks, voids, gaps, dislocations, shear bands, and combinations thereof. 
     
     
         10 . The composite of  claim 8 , wherein the base material has a thickness of 1 to 10,000 nm. 
     
     
         11 . The composite of  claim 8 , wherein the intermediate material has a thickness of 0.02 to 50 nm. 
     
     
         12 . The composite of  claim 8 , wherein the top material has a thickness of 1 to 10,000 nm. 
     
     
         13 . The composite of  claim 8 , wherein the intermediate material has a porosity of 1 to 75%.