Torayca

1. Tensile Strength
The tensile stress-strain curve of CF can roughly be considered to be linear, which means that strength and strain are proportional. 　　 For tougher fiber, and hence composite, higher strength (strain) is necessary. ‘TORAY’has been always keen to develop higher strength CF with adequately designed modulus.
Table represents mechanical properties of whole "TORAYCA" products. "TORAYCA" carbon fibers are classified in three general categories of products. 　　HT: High tensile strength with relatively medium young’s modulus (200-280GPa). 　　IM: Intermediate modulus fiber with young’s modulus range of around 300GPa. 　　HM: High modulus fiber with young’s modulus range over 350GPa. 　One of the most attractive properties of carbon fiber is its high strength fiber. Carbon fiber strand consists of several thousands of fine diameter (5-7micron) of single filament, therefore, when they are subjected to tensile load, failure is likely to initiate in a local region of single filament because of the influence of local value of filament and the geometry of that region. The typical structure of carbon fiber is illustrated in Fig.1-2.　Hence it is not practical to discuss tensile strength of carbon fiber itself. As the most of carbon fiber are used in a form of composite (carbon fiber reinforced plastics), nowadays, the tensile strength of carbon fiber is determined by the impregnated strand method (JIS-R-7601), which is a kind of composite tensile strength. 　　Since the introduction of T300 into the market in 1971, the tensile strength of carbon fiber has been drastically improved to meet the market requirements. Today, tensile strength of 6370MPa (T1000G) is available.