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.