Structure of carbon fibers o Turbostratic structure ● Fiber structure
Structure of carbon fibers ⚫ Turbostratic structure ⚫ Fiber structure
Carbon fibers Advantages of all carbon fibers o High tensile strength and tensile modulus ● Nonreactive Resistance to corrosion High heat resistance high tensile strength at elevated temperature o Low density
Carbon fibers – Advantages of all carbon fibers ⚫ High tensile strength and tensile modulus ⚫ Nonreactive – Resistance to corrosion – High heat resistance – high tensile strength at elevated temperature ⚫ Low density
Carbon fibers Disadvantages o High cost ● Brittle ● Oxidation at>400°C
Carbon fibers – Disadvantages ⚫ High cost ⚫ Brittle ⚫ Oxidation at > 400ºC
Carbon fibers o Other interesting properties Lubricating properties Electrical conductivity Thermal conductivit Low to negative thermal expansion coefficient
Carbon fibers ⚫ Other interesting properties – Lubricating properties – Electrical conductivity – Thermal conductivity – Low to negative thermal expansion coefficient
Difference between carbon fiber and graphite fiber ● Carbon fibers heat treatment below 1700 C less crystalline and lower modulus(365 GPa) ● Graphite fibers heat treatment above 1700 C More crystalline(80%)and higher modulus(365GPa
Difference between carbon fiber and graphite fiber ⚫ Carbon fibers – heat treatment below 1700°C less crystalline and lower modulus (<365 GPa) ⚫ Graphite fibers – heat treatment above 1700°C More crystalline (~80%) and higher modulus (>365GPa)