Title: carbon fibres type HT
Long Title: IUPAC Gold Book - carbon fibres type HT
DOI: 10.1351/goldbook.C00834
Status: current

Definition
Carbon fibres type HT are carbon fibres with values of Young's modulus between \(150\) and \(275\) to \(300\ \rm{GPa}\). The term HT, referring to high tensile strength, was early applied because fibres of this type display the highest tensile strengths.

Note
The disposition of boundaries between the fibre types is somewhat arbitrary. For carbon fibres type HT, the values of the strength-to-stiffness ratio are typically larger than \(1.5 \times 10^{-2}\). The tensile strength of carbon fibres is flaw-controlled, however, and therefore the measured values increase strongly as the diameter of the filaments is decreased.

Related Terms
- Young's modulus: https://goldbook.iupac.org//terms/view/M03966
- carbon fibres: https://goldbook.iupac.org//terms/view/C00831

Source
- PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 481 (https://doi.org/10.1351/pac199567030473)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C00834/html
- json: https://goldbook.iupac.org/terms/view/C00834/json
- xml: https://goldbook.iupac.org/terms/view/C00834/xml

Citation: Citation: 'carbon fibres type HT' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.C00834
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Accessed: 2026-07-14T22:59:00+00:00