GB/T 26749-2011 in English

《GB/T 26749-2011碳纤维 浸胶纱拉伸性能的测定》由TC572（全国碳纤维标准化技术委员会）归口，主管部门为国家标准化管理委员会。

Carbon fiber—Determination of tensile properties of resin-impregnated yarn
1 Scope
This Standard specifies a method of test for the determination of the tensile strength, tensile modulus of elasticity and strain at maximum load of a resin-impregnated yarn specimen.
The method is applicable to yarns (continuous and staple-fibre yarns) of carbon fibre for use as reinforcements in composite materials.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
ISO 291 Plastics-Standard atmospheres for conditioning and testing
ISO 527-1 Plastics-Determination of tensile properties-Part 1: General principles
ISO 1889 Reinforcement yarns-Determination of linear density
IS0 10119 Carbon fibre-Determination of density
IS0 10548 Carbon fibre-Determination of size content
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 527-1 and the following apply.
3.1
Cross-sectional area of carbon-fibre yarn (Af )
the linear density of the yarn divided by the density of the carbon fibre
Note: It is expressed in square millimetres (mm2).

Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 Principle
6 Equipment and reagents
7 Test specimen
8 Atmosphere for conditioning and testing
9 Tensile testing procedures
10 Expression of results
11 Precision
12 Test report
Annex A (Informative) Examples of heat-curable epoxy-resin systems
Annex B (Informative) Examples of impregnating apparatus
Annex C (Informative) Examples of extensometers
Annex D (Informative) Examples of tabs and tab-preparation apparatus