Deformation of two C36 Laves phases by microhardness indentation at room temperature

Microhardness indentation and electron microscopy were used to study the room-temperature deformation behavior of two Laves phases, ZrFe2 and MgNi2, in two-phase alloys. Evidence of extensive plastic deformation was found around the indentations. Activation of basal and nonbasal slip systems forms a distinctive cell structure in both Laves phases. Slip on planes nearly normal to the basal plane occurs in the lamellar form of ZrFe2. Burgers vectors of the dislocations and resulting shear displacements are studied using high-resolution transmission electron microscopy (TEM). Curved or zigzag nonbasal slip surfaces in atomic scale were observed. Each slip plane can be considered to be composed of a series of small facets of high atomic density. A common Burgers vector and displacement vector component of 1/4 [0001] was found on many different slip planes. The ''zonal glide'' concept for slip on prismatic planes is discussed