ISO 8256:2004 塑料-拉伸-冲击强度的测定
标准编号：ISO 8256:2004
中文名称：塑料-拉伸-冲击强度的测定
英文名称：Plastics — Determination of tensile-impact strength
发布日期：2004-07
标准范围
ISO 8256:2004规定了在规定条件下测定塑料拉伸冲击强度的两种方法（方法A和方法B）。这些试验可以描述为相对较高应变率下的拉伸试验。这些方法可用于刚性材料（如ISO 472所定义），但特别适用于柔性太大或太薄而无法通过符合ISO 179或ISO 180的冲击试验进行试验的材料。这些方法用于调查指定试样在指定冲击速度下的行为，并在试验条件固有的限制范围内估计试样的脆性或韧性。这些方法既适用于从模塑材料制备的试样，也适用于从成品或半成品（例如模塑件、薄膜、层压板或挤压或铸造板材）制备的试样。通过测试不同尺寸的模制试样获得的结果不一定相同。同样，从模制产品上切下的试样可能与直接从材料上模制的相同尺寸的试样产生的结果不同。从模塑化合物制备的试样中获得的试验结果不能直接应用于任何给定形状的模塑件，因为数值可能取决于模塑件的设计和模塑条件。方法A和方法B获得的结果可能具有可比性，也可能不具有可比性。这些方法不适合用作部件设计计算的数据源。然而，通过测试在不同条件下制备的不同类型试样，以及在不同温度下进行测试，可以获得有关材料典型性能的信息。这两种不同的方法既适用于生产控制，也适用于质量控制。
ISO 8256:2004 specifies two methods (method A and method B) for the determination of the tensile-impact strength of plastics under defined conditions. The tests can be described as tensile tests at relatively high strain rates. These methods can be used for rigid materials (as defined in ISO 472), but are especially useful for materials too flexible or too thin to be tested with impact tests conforming to ISO 179 or ISO 180.These methods are used for investigating the behaviour of specified specimens under specified impact velocities, and for estimating the brittleness or the toughness of specimens within the limitations inherent in the test conditions.These methods are applicable both to specimens prepared from moulding materials and to specimens taken from finished or semi-finished products (for example mouldings, films, laminates, or extruded or cast sheets).Results obtained by testing moulded specimens of different dimensions may not necessarily be the same. Equally, specimens cut from moulded products may not give the same results as specimens of the same dimensions moulded directly from the material. Test results obtained from specimens prepared from moulding compounds cannot be applied directly to mouldings of any given shape, because values may depend on the design of the moulding and the moulding conditions. Results obtained by method A and method B may or may not be comparable.These methods are not suitable for use as a source of data for design calculations on components. Information on the typical behaviour of a material can be obtained, however, by testing different types of test specimen prepared under different conditions, and by testing at different temperatures. The two different methods are suitable for production control as well as for quality control.
标准预览图
