Abstract
Strain-induced structural changes (SCs), which include chemical reactions (CRs) and phase transitions (PTs), are studied here numerically under compression and torsion of a sample in a rotational diamond anvil cell (RDAC). The results change the fundamental understanding of the interpretation of experimentally observed effects and measurements and the extraction of information on material behavior from system (sample) behavior. These effects include the nontrivial, nonlinear interaction between strongly heterogeneous stress and plastic strain tensor fields and SC kinetics, the effect of change of material strength during SC, the simultaneous occurrence of direct and reverse SCs in different regions, strong strain localization, and pressure self-multiplication.