4.6.3回弹性试验⑴试验目的回弹性是以规定的冲击质量和冲击速度使打击端的球面摆锤冲击试样时的恢复能与给予能之比。如本章4.2节所述,冲击和回弹的衰减角φ与回弹率R存在以下关系:R/100≈exp(-2πtanφ)因此,测定回弹率时可使用上式计算tanφ,而且可通过φ由下式计算损耗系数和对数衰减率,即: 4.6.3 Rebound test (1) Purpose of the test Rebound elasticity is the ratio of the recovery energy to the energy given when a spherical pendulum at the striking end impacts a specimen at a predetermined impact mass and impact velocity. As described in Section 4.2 of this chapter, the impact angle φ and the rebound angle φ have the following relationship with the rebound rate R: R / 100 ≈exp (-2πtanφ) Therefore, the tan φ can be calculated using the above formula for the spring rate, φ The loss factor and the logarithmic decrement are calculated by the following formula: