HOW NANOSCALE DIMENSIONS AFFECT PROPERTIES

MANY PROPERTIES ARE CONTINUOUSLY MODIFIED AS A FUNCTIONOF SYTEM SIZE. OFTEN THESE ARE EXTRINSIC PROPETIES, SUCH AS RESISTANCE, WHICH DEPEND ON THE EXACT SIZE AND SHAPE OF THE SPECIMEN. OTHER PROPERTIES DEPEND CRITICALLY ON THE MICROSTRUCTURE OF THEMATERIAL, FOR EXAMPLE, THE HALL PETCH EQUATION FOR YIELD STRENGTH, Q, OF A MATERIAL AS A FUNCTIONOF AVERAGE GRAIN SIZE (d) IS GIVEN


Q = k(d) ^1/2 + Qo

Kelsall, Nanoscale, p 24