What are the properties of nanocrystalline materials?
Nanocrystalline materials exhibit increased strength/hardness, enhanced diffusivity, improved ductility/toughness, reduced density, reduced elastic modulus, higher electrical resistivity, increased specific heat, higher thermal expansion coefficient, lower thermal conductivity, and superior soft magnetic properties in …
How are nanocrystalline materials made?
Nanocrystalline metals can be produced by rapid solidification from the liquid using a process such as melt spinning. This often produces an amorphous metal, which can be transformed into an nanocrystalline metal by annealing above the crystallization temperature.
What is nanocrystalline phase?
Nanocrystalline (NC) materials are single-phase or multiphase polycrystalline solids with a crystallite size of only a few nanometers (1 nm = 10− 9 m = 10 Å)—usually less than 100 nm. Grain sizes of 100–500 nm are classically considered “ultrafine” grains.
What is nanocrystalline technology?
NanoCrystal® is also a registered trademark of Elan Pharma International Ltd. (Ireland) for a technology that improves the bioavailability of drugs by rendering them as nanoscale particles that can be suspended in liquids, made into powder, pressed into tablets or encapsulated.
Why are nanocrystalline materials stronger?
Due to the small grain size, nanocrystalline materials often have superior properties to those of conventional polycrystalline coarse-grained materials. They exhibit increased strength, hardness, ductility, toughness, and reduced elastic modulus.
Who invented nanocrystalline?
Louis Brus
Around the same time, Louis Brus at Bell Labs was working on CdS colloids. Through a fine adjustment of growth conditions, he was able to control the size of these colloids and created nanocrystals that had diameters as small as 4.5 nm.
What is nanocrystalline solid?
Nanocrystalline solids are polycrystals, the crystal size of which is a few (typically 1 to 10) nanometres so that 50% or more of the solid consists of incoherent interfaces between crystals of different orientations.