Preferred Label : carbon fibres type HM;
IUPAC acronym : HM; UHM;
IUPAC definition : Carbon fibres type HM (high modulus) are carbon fibres with a value of Young's modulus
(tensile modulus) larger than 300 GPa (nearly 30% of the C11 elastic constant of a
graphite single crystal).;
Scope note : the level of the tensile modulus of carbon fibres is controlled by the degree of preferred
orientation of the layer planes in the direction parallel to the fibre axis. c11,
the elastic constant of graphite single crystals in the direction of the layer planes,
is 1060 20 1060 20 gpa. in general, the ratio of tensile
strength to tensile modulus is smaller than 1 10-2 for carbon fibres type hm (but
the tensile strength is influenced by flaws in the fibres and may be improved in the
future). carbon fibres type uhm (ultra-high modulus) have moduli of elasticity in
excess of 600gpa, surpassing 50% of the theoretical c11 number. such high values of
young's modulus can be achieved most readily in mesophase pitch-based carbon fibres
(mpp-based carbon fibres).;
Origin ID : C00833;
Automatic exact mappings (from CISMeF team)
- See also
Carbon fibres type HM (high modulus) are carbon fibres with a value of Young's modulus
(tensile modulus) larger than 300 GPa (nearly 30% of the C11 elastic constant of a
graphite single crystal).
