Wednesday, February 20, 2013

1302.4578 (Carlo Sasso et al.)

Finite element analysis of surface-stress effects in the Si
lattice-parameter measurement
   [PDF]

Carlo Sasso, Danilo Quagliotti, Enrico Massa, Giovanni Mana, Ulrich Kuetgens
A stress exists in solids surfaces, similarly to liquids, also if the underlying bulk material is stress-free. This paper investigates the surface stress effect on the measured value of the Si lattice parameter used to determine the Avogadro constant by counting Si atoms. An elastic-film model has been used to provide a surface load in a finite element analysis of the lattice strain of the x-ray interferometer crystal used to measure the lattice parameter. Eventually, an experiment is proposed to work a lattice parameter measurement out so that there is a visible effect of the surface stress.
View original: http://arxiv.org/abs/1302.4578

No comments:

Post a Comment