梁长对悬臂梁振动测定材料动弹性模量的影响

Effect of beam length on determination of dynamic elastic modulus of materials by means of cantilevel beam method

由悬臂梁振动测定材料动弹性模量的方法,受梁长与梁高比值的影响较为明显.选用有机玻璃和聚丙烯塑料2种材质,进行由悬臂梁振动测定材料动弹性模量试验.试验结果表明,只有当梁长大于或等于5倍梁高时,这种影响才可忽略不计.同时,当梁长大于或等于3倍梁宽时,对悬臂梁振动测定材料动弹性模量的影响不明显.

When the vibration test of cantilever beam samples is used for measurement of dynamic elastic modulus of materials, the influence of the ratio of beam length to beam height on the measured result can not be ignored. The measurement of the dynamic elastic modulus of two kinds of materials, i.e. organic glass and polypropylene plastic, with this method shows that the influence of the ratio can be neglected if the beam length is equal to or more than 5 times of the beam height, and that the influence of the ratio on the measured result is insignificant if the beam length is equal to or more that 3 times of the beam width.