本文件规定了通过线弹性断裂力学（LEMF）方法，在高达1 m/s的荷载点位移率下，确定裂纹张开模式（模式I）下塑料断裂韧性的原则和指南。本文件补充了ISO 13586，以便将其适用范围扩展到略高于后一文件范围的荷载率。 由于动态效应的存在，高加载速率下的断裂试验会出现特殊问题:试验系统中的振动会产生记录数量的振动，惯性载荷会在试样上产生与试验夹具感应到的力不同的力。这些影响需要加以控制，如果可能的话，通过适当的行动加以减少，或者通过对测量数据的适当分析加以考虑。 这种影响的相对重要性随着测试率的增加（测试持续时间的减少）而增加。当速度小于0.1 m/s（加载时间大于10 ms）时，动态效应可以忽略不计，ISO 13586中给出的测试程序可以按原样应用。当速度接近1 m/s（加载时间约为1 ms）时，动态效应可能会变得显著，但仍然可控。ISO 13586中给出的程序仍然可以使用，尽管有一些但书，本文件中也考虑了这些但书。在每秒数米及以上的速度下（加载时间明显短于1ms），动态效应占主导地位，需要采用不同的断裂韧性测定方法，这超出了本文件的范围。 除非本文件另有明确规定，否则ISO 13586中给出的低加载率断裂试验的一般原则、方法和规则仍然有效。 这些方法适用于ISO 13586涵盖的相同材料范围，即。 -刚性和半刚性热塑性模塑、挤压和铸造材料； -刚性和半刚性热固性模塑和铸造材料； 以及含有纤维的化合物≤ 7.5毫米长。 一般来说，已知长度为0.1 mm至7.5 mm的纤维会导致不均匀性和各向异性，尤其是在断裂过程中。因此，与ISO 13586:2018的附录B平行，本文件的相关附录C提供了一些指南，将相同测试程序的应用扩展到刚性和半刚性- 含有这种短纤维的硬质热塑性或热固性塑料。 尽管在高加载速率下发生的动态效应在很大程度上取决于所测试的材料以及所使用的测试设备和测试几何体，但此处给出的指南通常有效，无论测试设备、测试几何体和所测试的材料如何。 对于载荷-位移图的线性、试样尺寸和缺口尖端锐度，ISO 13586也有同样的限制。

This document specifies the principles and provides guidelines for determining the fracture toughness of plastics in the crack-opening mode (Mode I) by a linear elastic fracture mechanics (LEMF) approach, at load-point displacement rates of up to 1 m/s. It supplements ISO 13586 so as to extend its applicability to loading rates somewhat higher than is the case in the scope of the latter document. Fracture testing at high loading rates presents special problems because of the presence of dynamic effects: vibrations in the test system producing oscillations in the recorded quantities, and inertial loads producing forces on the test specimen different from the forces sensed by the test fixture. These effects need either to be controlled and, if possible, reduced by appropriate action, or else to be taken into account through proper analysis of the measured data. The relative importance of such effects increases with increasing testing rate (decreasing test duration). At speeds of less than 0,1 m/s (loading times of greater than 10 ms) the dynamic effects may be negligible and the testing procedure given in ISO 13586 can be applied as it stands. At speeds approaching 1 m/s (loading times of the order of 1 ms) the dynamic effects may become significant but still controllable. The procedure given in ISO 13586 can still be used though with some provisos and these are contemplated in this document. At speeds of several meters per second and higher (loading times markedly shorter than 1 ms) the dynamic effects become dominant, and different approaches to fracture toughness determination are required, which are outside the scope of this document. The general principles, methods and rules given in ISO 13586 for fracture testing at low loading rates remain valid except where expressly stated otherwise in this document. The methods are suitable for use with the same range of materials as covered by ISO 13586, i.e. — rigid and semi-rigid thermoplastic moulding, extrusion and casting materials; — rigid and semi-rigid thermosetting moulding and casting materials; and their compounds containing fibres ≤ 7,5mm in length. In general, fibres 0,1 mm to 7,5 mm in length are known to cause heterogeneity and anisotropy, especially significant in the fracture processes. Therefore, in parallel with Annex B of ISO 13586:2018, where relevant Annex C of this document offers some guidelines to extend the application of the same testing procedure, with some reservations, to rigid and semi-rigid thermoplastic or thermosetting plastics containing such short fibres. Although the dynamic effects occurring at high loading rates are largely dependent on the material tested as well as on the test equipment and test geometry used, the guidelines given here are valid in general, irrespective of test equipment, test geometry and material tested. The same restrictions as to linearity of the load-displacement diagram, specimen size and notch tip sharpness apply as for ISO 13586.