Prediction of Weld Quality by the Wave Propagation Modelling on Ultrasonic Testing Simulation

摘要

Computer simulation of ultrasonics is considered to be a very helpful toolto get information and physical understanding of wave phenomena inside thematerial, which can help to a suitable prediction of the service life of thecomponent. This simulation permits to establish a complete relation betweendifferent pulses in the A-scan signal.The ultrasonic testing of steel welds is a commonly used method in NDT.However, the analysis of the received signals, in a satisfactory way, is notsure. There is some uncertainty connected with testing techniques, likeerrors of characteristic measurement and influence of factors that cannot betaken into account for building up a model.As these factors cannot be evaluated a priori, and their combination canbring unpredictable influence on the testing results, it is possible torepresent them as additional noise response. And, since an incident wave ismodulated during travelling through the material, in a similar manner as aninput signal being modulated during passing through a system. So theincident and travelled waves can be considered as an input i (t) and outputfunctions o (t) of the system. Such an approach allows describing thematerial and testing as a united model, like in the case of dynamicmathematical modelling or system theory [1].In the present paper we try to simulate the propagation of the ultrasonicwave in a homogeneous material with the modelling of the system response, bythe use of the system theory.