Abstract: A series of single fiber tensile tests were conducted at 77K and room temperature for glass and
carbon fibers. The results show that at low temperature the statistical characteristics of the tensile strength can still be described by Weibull
distribution function and the average strengths are increased with different degree to the case of room temperature for both types of the fibers. The
scale parameter exhibits remarkable rising at 77K for glass fiber, while it is slight for carbon fiber. However, the shape parameters and tensile
modulus have no obvious change to the case of room temperature for both types of the fibers.

Key words: fibres, mechanical properties under low temperature, weibull distribution