초록 ▼

Silicon carbide fibers having an excellent mechanical strength and a superior heat resistance can be produced by the process in which activated carbon fibers having a thickness of 1 to 30 .mu.m and a BET specific surface area of 700 to 1500 m.sup.2 /g are reacted with a silicon and/or silicon oxide

Silicon carbide fibers having an excellent mechanical strength and a superior heat resistance can be produced by the process in which activated carbon fibers having a thickness of 1 to 30 .mu.m and a BET specific surface area of 700 to 1500 m.sup.2 /g are reacted with a silicon and/or silicon oxide gas at 1200 to 1500.degree. C. under a reduced pressure or in an inert gas atmosphere; and the resultant SiC fibers are heat treated in the presence of a boron-containing substance and optionally a carbon-containing substance at 1700 to 2300.degree. C. in an inert gas atmosphere, wherein the fibers may be in the form of a shaped article, for example, a sheet or honeycomb structure.

대표청구항 ▼

[ What is claimed is:] [1.]1. A process for producing silicon carbide fibers comprising the steps of:reacting activated carbon fibers having a fiber thickness of 1 to 30 .mu.m and a specific surface area of 700 to 1500 m.sup.2 /g determined by a BET nitrogen absorption method, with a gas comprising

[ What is claimed is:] [1.]1. A process for producing silicon carbide fibers comprising the steps of:reacting activated carbon fibers having a fiber thickness of 1 to 30 .mu.m and a specific surface area of 700 to 1500 m.sup.2 /g determined by a BET nitrogen absorption method, with a gas comprising at least one member selected from the group consisting of silicon and silicon oxides, at a temperature of 1200 to 1500.degree. C. under a reduced pressure of in an inert gas atmosphere, to convert the activated carbon fibers to silicon carbide fibers;applying boron to the silicon carbide fibers, to cause the boron to be carried on the silicon carbide fibers; and thenheat-treating the silicon carbide fibers carrying thereon boron at a temperature of 1900 to 2300.degree. C. in an inert gas atmosphere, to enhance the mechanical strength and heat resistance of the silicon carbide fibers.