Effect of the subsidiary misorientation components on the “special grain boundary-general boundary” transformation in the vicinity of the coincidence misorientation of Σ17 in tin

A small-angle twist or second tilt component was introduced to tilt boundaries [001] in tin bicrystals with misorientation angles 28.3°. The method of triple junction was used to measure the temperature dependences of the relative surface tension of the boundaries obtained and to determine the temperature of the “special boundary-general boundary” phase transition. The dependence of the transition temperature on the twist component θ_k and on the second tilt κ_H was found. The temperature of the grain-boundary phase transition, T_c, decreases with growing θ_k and θ_H, but several times slower than under deviation of the misorientation angle on the coincidence misorientation. The tilt component diminishes T_c slower than the twist component does. The results confirm the dislocation model of the “special boundary-general boundary” phase transition, proposed earlier.