1.1 本试验方法包括测定厚度为2.54至6.60 mm（0.100至0.260 in.）的平板状增强热固性塑料的面内剪切强度。本协议不适用于增强拉挤热固性产品，可使用试验方法 D2344/D2344M . 1.2 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 注1: 没有已知的ISO等效于本标准。 ====意义和用途====== 5.1 各种剪切试验广泛用于增强塑料行业，以评估聚酯、乙烯基酯和环氧树脂复合材料中增强材料与树脂的粘结强度。除了对生成用于研究和开发、质量控制和规范目的的数据的重要性外，此类测试对纤维增强行业具有根本价值，因为它们可以用于评估玻璃纤维表面处理的新型施胶系统的潜力。 5.2 该试验方法可用于确定具有随机分散纤维增强的层压板或其他增强塑料的剪切强度。 虽然该试验也适用于平行纤维增强塑料，但其设计适用于无法通过试验方法中所述的短梁程序进行满意试验的非平行纤维增强材料 D2344/D2344M .

1.1 This test method covers the determination of the in-plane shear strength of reinforced thermosetting plastics in flat sheet form in thicknesses ranging from 2.54 to 6.60 mm (0.100 to 0.260 in.). This protocol in not for reinforced pultruded thermoset products, which may use Test Method D2344/D2344M . 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Note 1: There is no known ISO equivalent to this standard. ====== Significance And Use ====== 5.1 Shear tests of various kinds are widely used in the reinforced plastics industry to assess the strength of the reinforcement-to-resin bond in polyester-, vinyl ester-, and epoxy-resin composites. In addition to their importance for the generation of data for research and development, quality control, and specification purposes, such tests are of fundamental value to the fibrous reinforcement industry, since they can be used to assess the potential of new sizing systems for the surface treatment of glass fibers. 5.2 This test method is useful for establishing the shear strength of laminates or other reinforced plastics having randomly dispersed fiber reinforcement. While the test also lends itself to parallel-fiber reinforced plastics, it has been designed to accommodate nonparallel-fiber reinforced materials that cannot be tested satisfactorily by the short-beam procedure described in Test Method D2344/D2344M .