Influence of heat-treatment and slurry on strength and distribution of Nextel 720 fiber

With two parameter Weibull distribution, the strength distribution of Nextel 720 fiber was investigated. And the fitness of the strength distribution was also conducted by the Kolmogorov test. With slurry infiltration, including silica sol, silica slurry and silicon nitride slurry, the influence of different slurry on the strength and distribution of Nextel 720 fiber were studied. Meanwhile, the influence of heat treatment was also performed. The results show that two parameter Weibull distributions can be used to present the strength distribution of Nextel 720 fiber. It also suggesting that the strength of the fiber decrease sharply after heat treated, and decen-trality of the strength is increased. Infiltrated with slurry and heat-treated at the temperature of 800°C, the strength of the fiber are much higher, and the Weibull modulus of the fibers are bigger than that of the as-received fiber tows. While treated at the temperature of 1000°C, the strength of the fiber tows are much lower due to the damage at higher treatment temperature. But the strength are still higher than that of the fiber tows' treated at same temperature without slurry, and the decentrality are also decreased.