<p><b>1.1 </b>This International Standard specifies a method for determining the in-plane shear modulus (<i>G</i>12) of fibrereinforced</p>
<p>plastic composites using a standard plate specimen. When applied to isotropic materials, the shear</p>
<p>modulus measured is independent of direction.</p>
<p><b>1.2 </b>The method is used to determine the shear modulus of the test specimens but not to determine the shear</p>
<p>strength. It applies to a plate supported on two points on one diagonal and loaded on the other diagonal by the</p>
<p>simultaneous movement of two loading points attached to a cross-beam.</p>
<p><b>1.3 </b>The method is suitable for use with fibre-reinforced plastic composites with both thermoset and thermoplastic</p>
<p>matrices.</p>
<p>Due to the shear deformation being applied under flexural conditions, for laminated materials with different fibre</p>
<p>formats and/or different orientations, the layers of material must be well distributed across the section so that it is</p>
<p>approximately "homogeneous" in the through-thickness direction.</p>
<p>The principal material axes, if present, must be orientated normal to the plate edges (see 3.8).</p>
<p>NOTE This method can be applied to unreinforced polymers and other materials (e.g. metals, ceramics and metal- or</p>
<p>ceramic-matrix composites).</p>
<p>For material fabricated using unidirectional plies, the shear modulus obtained using a multidirectional specimen</p>
<p>(i.e. 0°/90°/_ 45°) is not the same as that obtained for unidirectional or cross-ply (0°/90°) material.</p>
<p><b>1.4 </b>The method is performed using specimens which may be moulded to the chosen dimensions, machined from</p>
<p>test plates or machined from flat areas of products.</p>
<p><b>1.5 </b>The method specifies preferred dimensions for the specimen. Tests which are carried out on specimens of</p>
<p>other dimensions, or on specimens which are prepared under different conditions, may produce results which are</p>
<p>not comparable. Other factors, such as the speed of testing and the conditioning of the specimens, can influence</p>
<p>the results. Consequently, when comparative data are required, these factors must be carefully controlled and</p>
<p>recorded.</p>
<p>NOTE The stress-strain response in shear is very non-linear at higher strain levels. This test method determines the</p>
<p>modulus within a low strain region and is not applicable to higher strains.</p>
Registration number (WIID)
26468
Scope
<p><b>1.1 </b>This International Standard specifies a method for determining the in-plane shear modulus (<i>G</i>12) of fibrereinforced</p>
<p>plastic composites using a standard plate specimen. When applied to isotropic materials, the shear</p>
<p>modulus measured is independent of direction.</p>
<p><b>1.2 </b>The method is used to determine the shear modulus of the test specimens but not to determine the shear</p>
<p>strength. It applies to a plate supported on two points on one diagonal and loaded on the other diagonal by the</p>
<p>simultaneous movement of two loading points attached to a cross-beam.</p>
<p><b>1.3 </b>The method is suitable for use with fibre-reinforced plastic composites with both thermoset and thermoplastic</p>
<p>matrices.</p>
<p>Due to the shear deformation being applied under flexural conditions, for laminated materials with different fibre</p>
<p>formats and/or different orientations, the layers of material must be well distributed across the section so that it is</p>
<p>approximately "homogeneous" in the through-thickness direction.</p>
<p>The principal material axes, if present, must be orientated normal to the plate edges (see 3.8).</p>
<p>NOTE This method can be applied to unreinforced polymers and other materials (e.g. metals, ceramics and metal- or</p>
<p>ceramic-matrix composites).</p>
<p>For material fabricated using unidirectional plies, the shear modulus obtained using a multidirectional specimen</p>
<p>(i.e. 0°/90°/_ 45°) is not the same as that obtained for unidirectional or cross-ply (0°/90°) material.</p>
<p><b>1.4 </b>The method is performed using specimens which may be moulded to the chosen dimensions, machined from</p>
<p>test plates or machined from flat areas of products.</p>
<p><b>1.5 </b>The method specifies preferred dimensions for the specimen. Tests which are carried out on specimens of</p>
<p>other dimensions, or on specimens which are prepared under different conditions, may produce results which are</p>
<p>not comparable. Other factors, such as the speed of testing and the conditioning of the specimens, can influence</p>
<p>the results. Consequently, when comparative data are required, these factors must be carefully controlled and</p>
<p>recorded.</p>
<p>NOTE The stress-strain response in shear is very non-linear at higher strain levels. This test method determines the</p>
<p>modulus within a low strain region and is not applicable to higher strains.</p>
