Units

In Metafor, as in most FE codes, units are not explicitly defined. The user must enter input data in a consistent way.

	SI	SI (mm)
Length	$\mbox{m}$	$\mbox{mm}$
Force	$\mbox{N}$	$\mbox{N}$
Mass	$\mbox{kg}$	$\mbox{tonne}$
Time	$\mbox{s}$	$\mbox{s}$
Stress	$\mbox{Pa } \left ( \mbox{N}/\mbox{m}^2 \right ) $	$\mbox{MPa } \left ( \mbox{N}/\mbox{mm}^2 \right ) $
Energy	$\mbox{J}$	$\mbox{mJ } \left ( 10^{–3} \mbox{J} \right ) $
Density	$\mbox{kg/m³}$	$\mbox{tonne} / \mbox{mm}^3$

For example, if the geometry (point coordinates) is expressed in meters and the boundary conditions (loads) in Newton, the Young's Modulus appearing in the material definition must be expressed in $\mbox{N/m}^2$. Likewise, a geometry in meters and a Young's Modulus in $\mbox{kg/m}^2$ lead to forces in $\mbox{kg}$.