ISO 6943:2017规定了一种测定硫化橡胶在反复拉伸变形下抗疲劳性的方法，试样尺寸和循环频率应确保几乎没有或没有温升。在这些条件下，失效是由裂纹的扩展导致的，裂纹最终会切断试件。 该方法仅限于重复变形，其中试件在每个循环的一部分放松至零应变。在不通过零应变的重复变形下，以及在某些橡胶中，在静态变形下，可能会发生类似的疲劳过程，但本文件不适用于这些条件。 该方法被认为适用于至少在循环一段时间后具有合理稳定的应力-应变特性，且不表现出过度应力软化或凝固或高粘性行为的橡胶。 从实验和解释的角度来看，不符合这些标准的材料可能会带来相当大的困难。例如，对于在疲劳试验期间产生大量凝固的橡胶，在恒定最大载荷和恒定最大延伸条件下，试验应变将不明确，疲劳寿命可能显著不同；如何解释这种橡胶的结果，或将其与其他橡胶的结果进行比较，尚未通过基础工作确定。作为一般指南，根据9.5和10.2确定的橡胶组超过10%可能属于该类别。因此，该方法不适用于大多数热塑性弹性体。 类似的考虑也适用于测试期间弹性行为的其他变化。 该疲劳试验不同于ISO 4666各部分中所述的挠曲仪试验，其中疲劳破坏是在应力和温度的同时作用下发生的。 与De Mattia弯曲开裂和切口生长试验（见ISO 132）相比，其优点包括: -测试产生的定量结果不依赖于操作员的解释，可以自动记录； -初始变形是明确定义的，可以很容易地改变，以适应不同的应用。 在尝试将标准试验结果与使用性能联系起来时，必须格外小心，因为不同硫化胶的相对抗疲劳性可能会因所用试验条件和结果比较依据的不同而不同。附录A中给出了试验条件选择和结果解释指南。

ISO 6943:2017 specifies a method for the determination of the resistance of vulcanized rubbers to fatigue under repeated tensile deformations, the test piece size and frequency of cycling being such that there is little or no temperature rise. Under these conditions, failure results from the growth of a crack that ultimately severs the test piece. The method is restricted to repeated deformations in which the test piece is relaxed to zero strain for part of each cycle. Analogous fatigue processes can occur under repeated deformations which do not pass through zero strain and also, in certain rubbers, under static deformation, but this document does not apply to these conditions. The method is believed to be suitable for rubbers that have reasonably stable stress-strain properties, at least after a period of cycling, and that do not show undue stress softening or set, or highly viscous behaviour. Materials that do not meet these criteria might present considerable difficulties from the points of view of both experiment and interpretation. For example, for a rubber that develops a large amount of set during the fatigue test, the test strain will be ill-defined and the fatigue life is likely to differ markedly under constant maximum load and constant maximum extension conditions; how the results for such a rubber should be interpreted or compared with those for other rubbers, has not been established by basic work. As a general guide, a rubber for which the set determined in accordance with 9.5 and 10.2 exceeds 10 % is likely to fall into this category. For this reason, the method is not considered suitable for most thermoplastic elastomers. Similar considerations apply with regard to other changes in elasticity behaviour during testing. This fatigue test is distinct from the flexometer tests described in the various parts of ISO 4666, where fatigue breakdown occurs under the simultaneous action of stress and temperature. Advantages over the De Mattia flex cracking and cut growth test (see ISO 132) include the following: - the test yields quantitative results which do not depend on operator interpretation and which can be recorded automatically; - the initial deformation is clearly defined and can readily be varied to suit different applications. Great caution is necessary in attempting to relate standard test results to service performance since the comparative fatigue resistance of different vulcanizates can vary according to the test conditions used and to the basis by which the results are compared. Guidance on the selection of test conditions and on the interpretation of results is given in Annex A.