A text I read had this line: "finer crystal structure for better performance".
After a lot of thinking it seemed as if the author meant about the finer grain structure. How should this confusion be deciphered?
Hi Saransh,
I think that the major difference is that the term "grain" is more used in metallurgie and the term "crystal" is more used in the physico-chemical domain. However ther are some differences about this two terms. A crystal has a unique arrangement of molecules or atoms an a lattice showing a symmetry and long range order (usually a three-dimensional arrays of atoms). Thus a crystal is a unit lattice in wich atoms are arranged in a specific position. A grain is a bunch of crystals (rather than a unit lattice) arranged in a same direction. When small crystalls growth they can form a polycrystaline structure in wich the small crystals are calling grains. Every small crystal is a true crystal but the whole polycrystal does not have a periodic arrangement because the periodic pattern is broken at the grain boundaries.
Depends on the topic. As you know crystals have a a very ordered structure that theorically is infinite. Practically as nucleation centers start their growth form cristalline grains because in the growing they meet each other after some time. The nucleation and growth conditions and growth are dominant on the grain dimensions. This thing is very common in electroplating of metals. It is well known from technicians that high current densities in the plating create a great numbers of nucleation centers and makes finer grains. The "better performances" are always bonded to the specific application of the realized structure. In galvanic finer grains bring to harder and more compact structures.
Hi Saransh,
I think that the major difference is that the term "grain" is more used in metallurgie and the term "crystal" is more used in the physico-chemical domain. However ther are some differences about this two terms. A crystal has a unique arrangement of molecules or atoms an a lattice showing a symmetry and long range order (usually a three-dimensional arrays of atoms). Thus a crystal is a unit lattice in wich atoms are arranged in a specific position. A grain is a bunch of crystals (rather than a unit lattice) arranged in a same direction. When small crystalls growth they can form a polycrystaline structure in wich the small crystals are calling grains. Every small crystal is a true crystal but the whole polycrystal does not have a periodic arrangement because the periodic pattern is broken at the grain boundaries.
Saransh, Grain contains a unique crystal structure. means crystal structure is part or base of grain. And crystal is somewhat homogeneous structure and has fixed distance and angle between atom and molecules, like Regular pattern. e.g. Simple cubic, FCC, BCC, FCC, HCP.
Now, grain is main and base part of micro structure of any metal. grain size depends on lots of parameters. but imp. is manufacturing technique, heat treatment and service conditions........
as the grain size is finer, more strong materials
The dilema seems reasonable.Still, maybe these "crystalites" are more or less regulatate - them being in fact grains. But, for beter crystaline structure of the crystalites, the material shows improved performance.
Anyway, what I'm trying to say is that there are very few crystals that are in fact flawless - defaults being almost always present.
But the details are scarce - it can be easily taken out of context!
- Badges
- Science topic
- Similar topics
- Engineering