Formation of nano-sized crystals during plastic deformation in amorphous alloys

Microstructural change in deformation bands was observed in a Ni-P amorphous alloy using transmission electron microscopy (TEM). Bending strain was applied to a micro-sized cantilever beam specimen. A TEM specimen was prepared from the micro-sized specimen with keeping the information on the relationship between the deformed direction and the specimen orientation. TEM observation in deformation bands revealed that plastic deformation induces the precipitation of nanocrystalline Ni particles. An orientation relationship between deformation direction and crystal orientation was obtained, that is, a (111) plane of all crystalline particles are parallel to the side surface of the specimen.