Electron microscopy investigation of the surface relief after concentrated load deformation of NaCl crystals

The investigation by electron microscopy of the relief change after indentation reveales new peculiarities of the plastic deformation in NaCl crystals. The formation of hillocks near the indentation and on a lateral surface was observed. The hillocks are oriented in 〈110〉 directions, coinciding with the directions of chains of similar ions in the crystal. The formation of hillocks may be explained by the motion of interstitial ions by means of crowdions, their coagulation into prismatic dislocation loops, and their emergence at the surface by means of the joint action of prismatic slip and climb.