X-ray line broadening and stored energy in deformed and annealed calcite

Abstract

Abstract Plastic deformation of calcite aggregates leads to greater x-ray line broadening and stored energy than for many polycrystalline metals at similar strains. On heating, both quantities are reduced and distinct recovery and recrystallization stages are observed. The activation energy for recrystallization (110 kcal mole−1) is very high compared with metals. The line broadening appears to be due mainly to internal strains but the elastic strain energy calculated from the x-ray line broadening for a simple internal strain model accounts for about 30% of the measured stored energy of 1–2 cal per g.