Boron and boron carbide coatings by vapor deposition.
Metall Trans 1970 Oct; 1(10):2875-2880
The Bureau of Mines investigated the formation of boron and boron- carbide coatings by vapor-phase reactions. Optimum parameters were determined for hydrogen reduction of boron trichloride and for the formation of boron-carbide coatings on graphite by reaction with the depositing boron. At 1,300 deg. C, about 85 percent of the boron was deposited. Tungsten substrates did not react with the boron deposit; other substrates reacted to various extents. The hydrogen reduction of boron tribromide was briefly investigated. Boron carbide was deposited at 1,300 deg. C by adding methane to the boron trichloride-hydrogen feed gas. The chemical composition of the vapor-deposited boron carbide approximated b4c. A method of etching b4c was developed to study its microstructure. When boron was deposited on graphite at 1,500 deg c, very hard, uniform, strongly adherent coatings of b4c were formed that might be useful in applications such as rocket nozzles and chemical reaction and processing vessels.
Boron-compounds; Chemical-reactions; Chemical-processing; Metal-compounds; Metal-carbides; Metallic-compounds
10294-34-5; 7440-42-8; 74-82-8; 7782-42-5; 7440-33-7
OP; Journal Article
Metallurgical Transactions. B. Process Metallurgy