Objective As key factors affecting the axial impact performance (AIP) of cutting-type energy-absorbing tubes (CEAT), material fracture failure parameters directly determine the stability of axial impact force and the curling-separation mode of chips. Therefore, it is necessary to investigate the AIP of CEAT from the perspective of material fracture failure parameters.
Method Tensile fracture tests are carried out on three typical notched specimens to obtain the fracture strain of the material under different stress states. Furthermore, the tensile fracture tests of the three specimens are simulated using finite element method, and the average stress triaxiality of the specimens is obtained. A material fracture failure model based on the Johnson-Cook model is fitted accordingly. Finite element simulations of axial impact on CEAT are conducted, and the accuracy of the model is verified by comparing simulation results with impact test data. On this basis, the effects of cutting depth and cutting width on the AIP of CEAT are further studied.
Result & Conclusion The fitted Johnson-Cook material fracture failure model can effectively simulate the cutting-curl mode of CEAT, yielding stable and accurate cutting force. The peak cutting force and average cutting force are positively correlated with cutting depth; the average force increases by approximately 76.3 kN for every 0.4 mm increase in cutting depth. With the increase of cutting width, both the peak force and average force will rise, while the growth rate gradually decreases.
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