本文研究并应用双梁振动法测定复合材料的动态弯曲模量E_(Db)。此法不需测定材料的力与变形关系便能得到弯曲模量。在单向复合材料测试中,它能避免90°方向试件常出现容易损坏而使实验无法进行的缺点。与其他试验方法相比,双梁振动法原理简单、测定准确、材料运用性广、投资少、使用方便。 In this paper, the dynamic bending modulus E_ (Db) of composites was studied and measured by double-beam vibration method. This method does not need to measure the force and deformation of the material can be flexural modulus. In the unidirectional composite testing, it can avoid the shortcoming that the specimen in the 90 ° direction can easily be damaged and the experiment can not be performed. Compared with other test methods, double girder vibration method is simple in principle, accurate in measurement, wide in material utilization, less in investment and convenient in use.