Adiabatic Shear Band Formation In Metal Cylinder

Adiabatic shear band is one important mechanism of material’s failure. Although manyresearch about adiabatic shear localization were launched by experimental and theoretical study,there are many problems in engineering and numerical simulation, especially there is few methodto predict and control multiple adiabatic shear bands effectively. So it has important academic andengineering significance to research multiple adiabatic shear bands.In this paper, experimental and numerical study is launched to study multiple adiabatic shearbands in thick-walled cylinder compression. Pulse electromagnetic compression experimentaltechniques are discussed, and the critical criterion and influencing factors of shear band formationare discussed by finite element method. There are several conclusion:(1) material constitutiveinstability criterion is not sufficient condition for shear band formation, and shear band is formedafter critical point. Stress collapse and strain explosive growth will occur when shear band isformed.(2) Elastic unloading occurs beside the shear band when shear band is formed.(3)Thebaseline criterion is presented in this paper, and we find that the number of shear bands by Batracriterion is less than baseline criterion, which means some shear band will stop while others willstill grow.(4) Thermal softening parameters obtained by experimentation is not enough to describethe material property in the shear band.(5)With the improvement of the loading rate, the initialstrain of shear band shows a downward trend, and the spacing decreases.(6)With the increase ofmaterial softening, the initial strain of shear band also decreases and the number of shear bandsincreases.