On the Critical Nominal Strain in Adiabatic Shear Banding
نویسندگان
چکیده
The attention is focused on the influence of boundary conditions on the critical nominal swain to failure in adiabatic shear banding. First, the influence of mixed velocity-stress conditions for a Knowles constitutive law is investigated, then stress controlled and velocity controlled conditions are discussed for a multiplicative power law form. It is shown with an analyticaVnumerical method that the critical strain is not sensitive to the boundary condition when a Knowles constitutive relation is used, but that it is less under stress controlled conditions than for velocity boundary conditions, when a multiplicative form of the thermoviscoplastic constitutive law is employed. R6um6. On s'intiresse h I'influence de conditions aux limites sur la diformation nominale critique A rupture en cisaillement adiabatique. Dans un premier temps, I'influence des conditions de chargernent mixtes pour la fonction de Knowles est ttudiie, ensuite les contr6les en vitesse et en contrainte sont discutis pour une loi puissance multiplicative. I1 est rnontri avec une mithode analytiquelnurnirique que la contrainte critique est insensible aux conditions aux limites quand une loi de comporternent de Knowles est utilisie, mais qu'elle est plus faible sous un contrBle en vitesse que sous un contr6le en contrainte lorsque une forme multiplicative de la loi thermoviscoplastique est employte.
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