The Research Of Steel Plates Stress Testing Technology Base On Ultrasonic

With the development of industrial technology, steel material has been more and morewidely applied in various fields. Because in the production processing and materialhandling process, material internal local area produce non-uniform plastic deformation,will produce stress. While the presence of stress often leads to the occurrence of majoraccidents. Therefore, the safety of steel material takes more and more attention. At presentthe stress testing methods divided to damage detection and non-destructive testing, thestress test methods are divided into damage detection and nondestructive testing, damagedetection make destructive to the detected work-piece, non-destructive testing not only hasdamage, but also has many methods. Stress testing based on ultrasonic plate belongs tonon-destructive testing, longitudinal sensitive to stress, the detection sensitivity is high, canbe more accurate test out surface tangential stress and residual stress. On the steel materialstress testing plays a warning to avoid accidents role, so ultrasonic stress testing also getmore and more attention.In order to obtain the effect of steel plates stress to ultrasonic transmission properties,test the relationship between stress and velocity, apply ANSYS/LS-DYNA nonlinear finiteelement dynamic analysis unit, implicit-explicit analysis method realize steel plate stressdetected by forced variable wave simulation ultrasonic propagation simulation, compare tothe ultrasonic propagation characteristic influence of steel plate which has stress or nostress in. Studies the basic principle of ultrasonic testing stress respectively, compare theeffect of detect stress based on longitudinal wave method, shear wave method, the surfacewave method, choose the critical refraction longitudinal wave method which is higherdetection sensitivity, deeper propagation depth. Based on the study of organic glass wedgeblock, design out of the critically refraction longitudinal wave emission probe model, andapplied in the experimental verification.Theoretical analyses show that the applied stress in steel plate under the condition ofultrasonic propagation speed, larger, and applying a tensile stress when the velocity of. Byusing ANSYS finite element simulation analysis of plate exerts compressive stress in steel plate, ultrasonic propagation speed influence. The plate has a stress free vibration analysis,respectively on three kinds of wave plate node displacement and stress are analyzed, thecalculated results of the wave propagation speed, to exert a compressive stress, velocityincreases. On the basis of simulation, verified by experiments, experimental verifycritically refraction longitudinal wave theory, and through the standard steel plate and theapplied stress steel plate detection results, obtained the stress in steel plate, ultrasonic wavevelocity showed a trend of increase, and the theory and the simulation is consistent.