Abstract:
Q345 steel has been widely used in many fields, but there is still a lack of reliable method for real-time and online monitoring damage, and therefore Acoustic Emission (AE) technology is presented for dynamic monitoring of crack growth process in Q345 steel. Firstly, specimens of the steel are designed according to the test equipment. And then tensile and three point bending experiments to the specimen are completed by electronic testing machine, and AE signals are collected by AE instrument during the course of crack changing process. And finally, characteristics parameters are extracted from acoustic emission signals and the changing law of counting and energy to time is researched by using the experience of the graph, and changing state of specimen crack can be evaluated from the change law. The experimental results show that the AE characteristic parameters have different performance characteristics in different initiation, propagation and fracture stages of the specimen, and the damage status of Q345 steel can be evaluated through the two characteristic parameters.