ISO 527-4:1997 pdf download – Plastics – Determination of tensile properties – Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites.
3 Principle See IS0 527-1, clause 3. 4 Definitions For the purposes of this part of IS0 527, the following definitions apply. 4.1 gauge length: See IS0 527-1, subclause 4.1. 4.2 speed of testing: See IS0 527-l) subclause 4.2. 4.3 tensile stress, cr (engineering): See IS0 527-1, subclause 4.3, except that CT for “l”-direction specimens is defined as 01 and for “2”-direction specimens as cr2 (see 4.8 for definitions of these directions). 4.3.1 tensile strength, 0~: See IS0 527-1, subclause 4.3.3, except that oM for “1”-direction specimens is defined as ml and for “P-direction specimens as c$&. 4.4 tensile strain, E: See IS0 527-1, subclause 4.4, except that E for “1’‘-direction specimens is defined as ~1 and for “2”-direction specimens as ~2. It is expressed as a dimensionless ratio or in percent. 4.5 tensile strain at tensile strength; tensile failure strain, &M: The tensile strain at the point corresponding to the tensile strength of the specimen. For “1’‘-direction specimens, EM is defined as ~1 and for “2”-direction specimens as &t&J. It is expressed as a dimensionless ratio or in percent. 4.6 modulus of elasticity in tension; Young’s modulus, E: See IS0 527-1, subclause 4.6, except that E for “l”-direction specimens is defined as Et and for “T-direction specimens as E2. The strain values used are as given in IS0 527-1, subclause 4.6, i.e. E’ = 0,000 5 and E” = 0,002 5 (see figure l), unless alternative values are given in the material or technical specifications. 4.7 Poisson’s ratio, ,u: See IS0 527-1, subclause 4.7, except that for “1’‘-direction specimens pb is defined as ~12 and j& as ~13, using the coordinates shown in figure 2. For “2”-direction specimens, ,q, is defined as ~21 and jam as ,u23-
6 Test specimens 6.1 Shape and dimensions Three types of test specimen are specified for use with this part of IS0 527, as detailed and illustrated in figure 3 (type 1 B) and figure 4 (types 2 and 3). Type 1 B is for testing fibre-reinforced thermoplastics. Type 1 B specimens may also be used for fibre-reinforced thermosets if they break within the gauge length. Type 1 B shall not be used for multidirectional, continuous-fibre- reinforced materials. Type 2 (rectangular without end tabs) and type 3 (rectangular with bonded end tabs) are for testing fibre-reinforced thermosets and thermoplastics. Specimens with unbonded end tabs are considered as type 2. The preferred width of type 2 and type 3 specimens is 25 mm, but widths of 50 mm or greater may be used if the tensile strength is low due to the particular type of reinforcement used. The thickness of type 2 and type 3 specimens shall be between 2 mm and 10 mm. To decide whether to use type 2 or type 3 specimens, first carry out tests with type 2 specimens and, if the test is not possible or not satisfactory, i.e. if the specimen slips or breaks in the grips (see IS0 527-1, subclause 5.1), use type 3 specimens. For compression-moulded materials, the thickness between the end-pieces of any type of specimen shall at no point deviate from the mean by more than 2 %.