Thermal and electrical conductivity of grain boundaries in metals with bcc and fcc crystal lattices

This study employs first-principles calculation methods to investigate the thermoelectric properties of high-angle grain boundaries in metals (iron, titanium, copper, and nickel) with symmetric tilt boundaries of two types of crystal  lattice: body-centered cubic and face-centered cubic. Grain boundaries play a significant role in carrier and phonon transport in materials. Altering geometric parameters is one of the simplest ways to control thermoelectric characteristics. By varying the grain rotation axis, rotation angle, and grain self-orientation, we derived the dependence of the electrical and thermal conductivity of studied materials on the geometry of the modeled device at room  temperature. The results presented in the work can give an idea of the effect of this type of surface defect on thermal and electrical conductivity.