"mac davis" wrote in message
...
On Mon, 8 Feb 2010 22:52:24 -0800, "Bill Noble"
wrote:

snip


Bill.. Is "nano grain" or whatever they call it just a marketing thing, or
does
it actually have smaller grain for a sharper edge?


mac


well, that sounds like a fun research project - the way you heat treat the
material affects grain size -it's been a very long time since those classes

I did find this abstract, though I must admit to not reading the article

Abstract Dense nanocrystalline BaTiO3 (BT) ceramics with grain size (GS) 50
nm were successfully prepared by spark plasma sintering (SPS) method. The
nanoindentation experiment was used to test the hardness of different GS BT
ceramics. It was found that the hardness of 50 nm nanograin BT ceramics
increased 82% than that of 1.2 μm BT ceramics fabricated by conventional
sintering (CS) process. Dislocation pinning resulting from the increase of
grain boundary by ultrafine GS are believed to be the dominant factor in
raising strength. Restriction on dislocation generation and mobility due to
the domain wall motion and sliding imposed by ultrafine GS are expected to
be exceptionally important. At the same time, the large stress in nanograin
BT ceramics may also play a role in producing high strength. These
differences of the hardness behavior between BT ceramics are attributed to
the variation of the resultant microstructure, especially the GS of the
ceramics.