This standard describes a method for the determination of certain tensile characteristics of glass fiber reinforced plastics. This method is not necessarily applicable to materials with very high tensile strength, for example to unidirectional reinforced materials. This standard is applicable to thermosetting and thermoplastic resins reinforced with glass fibres. Injection molded glass fiber reinforced thermoplastic tubes are subject to fiber orientations and may give abnormally high values; however, they can be used when other preparation methods cannot be used. 2 The method allows the following tensile characteristics to be determined:
——initial tangent elasticity modulus and secant elasticity modulus (when it is not possible to determine the initial tangent elasticity modulus, the secant modulus at 0.1% elongation is determined);
——maximum unit load; Note - In case of net failure, this maximum unit load is the unit load at failure, otherwise it is the unit load corresponding to the maximum load. — elongation under the maximum load and possibly elongation at break. The load - elongation curves, which can be carried out at different temperatures, humidity and tensile speeds, provide interesting indications about the behavior of the materials. 3 If identical test tubes are not used, it is not possible to obtain comparative values between different materials. The test pieces must also be tested under well-defined preliminary conditioning conditions (temperature, humidity and tensile speed). Finally, the method aims to obtain tensile test results that can be used:
——for quality controls or — to establish specifications for materials.
UNI EN 61-1978 history
1978UNI EN 61-1978 Glass reinforced plastics. Determination of tensile properties.