Analysis and attenuation of disturbance vibrations in notched bar impact testing

摘要

In order to estimate the fracture behaviour of metal under the influence of the main test parameter temperature and high deformation velocity at the presence of a notch the notched bar impact testing is performed. In this experiment the dynamic load-time and load-displacement relationship is evaluated by means of an instrumented pendulum Charpy machine. Based on this diagram it is possible to intensively judge material properties, e.g. loads or deflection at general yield and at initiation of ductile fracture or the respective values at cleavage fracture.[1] A typical transient load-time-diagram is shown in Fig.1. It is obvious that disturbance vibrations with high frequencies are superposed on the transient load-time record. These disturbances could considerably impede the evaluation of important values in the fully plastic regime. Besides this these disturbances may influence the actual effective load of sample, so that not only shock load but combined shock and vibration-load is acting.