ISO 180-2019 pdf free.Plastics – Determination of Izod impact strength. 1.4 The method is not normally suitable for use with rigid cellular materials and sandwich structures containing cellular material. Notched specimens are also not normally used for long-fibre-reinforced composites or thermotropic liquid-crystal polymers. 1.5 The method is suited to the use of specimens which can be either moulded to the chosen dimensions, machined from the central portion of a standard multipurpose test specimen (see Iso 20753) or machined from finished or semi-finished products such as mouldings, laminates and extruded or cast sheet. 1.6 The method specifies preferred dimensions for the test specimen. Tests which are carried out on specimens of different dimensions or with different notches, or specimens which are prepared under different conditions, may produce results which are not comparable. Other factors, such as the energy capacity of the apparatus, its impact velocity and the conditioning of the specimens can also influence the results. Consequently, when comparative data are required, these factors are to be carefully controlled and recorded. 1.7 The method is not intended to be used as a source of data for design calculations. Information on the typical behaviour of a material can be obtained, however, by…