Study on the Cracking Time in Low-stress Precision Cropping Based on Acoustic Emission Technology

Abstract

The high-speed centrifuge and low-stress precision cropping is the technology which makes use of the stress concentration effect of the prefabricated V-shaped groove on the surface of the metal bar and relies on the expansion of the crack to achieve precision cropping. This paper applies the acoustic emission testing technology to monitor the entire process of low-stress precision cropping in order to solve the problem that the cracking time of V-shaped groove tip cannot be precisely determined during the low-stress cropping. It is concluded that the acoustic emission signal can be used to describe the crack damage process of V-shaped groove tip, providing better cross-section quality. Based on this, the cracking time of V-shaped groove tip is further determined, which better meets the requirements of low-stress precision cropping.