Dislocations in plastically deformed apatite

Dislocations were introduced at room temperature by a Vickers indentation into a biological ceramic, apatite. Two types of apatite, a single crystal of fluorapatite and a sintered polycrystal of hydroxyapatite, were studied. Specimens prepared using a focused-ion-beam technique were examined by transmission electron microscopy. Natures of dislocations were determined by the conventional g · b criterion, where the weak-beam method was also applied. The slip system in fluorapatite apatite was determined to be