A method of curing a polysilazane fiber, comprising: a) forming a polysilazane fiber by: i. reacting at least one methylchlorodisilane; at least one organochlorosilane comprising at least one alkenyl group, wherein said at least one alkenyl group is selected from allyl, acrylate, methacrylate, vinylether, or styryl; and at least one nitrogen-containing additive, to form a resin; ii. combining the resin with at the least one free-radical generator, wherein said free radical generator is selected from a peroxycarbonate, a peroxysiloxane, and an azo-containing compound and optionally at least one inhibitor, to form a resin mixture; and iii. spinning said resin mixture to form said polysilazane fiber, wherein said spinning is performed at a temperature below the 1 h half-life temperature of the free radical generator; b) exposing the polysilazane fiber, to moisture at greater than 1% relative humidity; and c) curing said polysilazane fiber by exposing said polysilazane fiber to a temperature above the 1 h half -life temperature of the free radical generator, which is the temperature at which 50% of the free radical molecules undergo decomposition to form free radicals in one hour, but below the softening point temperature of the moisture-exposed polysilazane fiber. a) forming a polysilazane fiber by: i. reacting at least one methylchlorodisilane; at least one organochlorosilane comprising at least one alkenyl group, wherein said at least one alkenyl group is selected from allyl, acrylate, methacrylate, vinylether, or styryl; and at least one nitrogen-containing additive, to form a resin; ii. combining the resin with at the least one free-radical generator, wherein said free radical generator is selected from a peroxycarbonate, a peroxysiloxane, and an azo-containing compound and optionally at least one inhibitor, to form a resin mixture; and iii. spinning said resin mixture to form said polysilazane fiber, wherein said spinning is performed at a temperature below the 1 h half-life temperature of the free radical generator; i. reacting at least one methylchlorodisilane; at least one organochlorosilane comprising at least one alkenyl group, wherein said at least one alkenyl group is selected from allyl, acrylate, methacrylate, vinylether, or styryl; and at least one nitrogen-containing additive, to form a resin; ii. combining the resin with at the least one free-radical generator, wherein said free radical generator is selected from a peroxycarbonate, a peroxysiloxane, and an azo-containing compound and optionally at least one inhibitor, to form a resin mixture; and iii. spinning said resin mixture to form said polysilazane fiber, wherein said spinning is performed at a temperature below the 1 h half-life temperature of the free radical generator; b) exposing the polysilazane fiber, to moisture at greater than 1% relative humidity; and c) curing said polysilazane fiber by exposing said polysilazane fiber to a temperature above the 1 h half -life temperature of the free radical generator, which is the temperature at which 50% of the free radical molecules undergo decomposition to form free radicals in one hour, but below the softening point temperature of the moisture-exposed polysilazane fiber.