Characteristics study of thin-walled circular copper tubes for impact transformation

An axial bulking mode of the thin-walled tube is proposed and investigated experimentally, for the purpose of transforming a pulse impact into a controllable impact. Two types of thin-walled circular copper tubes with different structures are designed based on the basic circular tubes (BCTs), namely, the uniform grooved tube (UGT) and the circumferential opening grooved tube (CGT). Then, the impact characteristics of a series of copper tubes are investigated experimentally. Results show that BCTs are compressed into two-fold forms during impact, where compression deformation occurs at the thin-walled section and a fold is formed at each thin-walled section. BGTs, UGTs, and CGTs show different performances in terms of transforming impact, and impact output via CGT can be controlled by modifying its structural parameters.