# OOF: Finite Element Analysis of Microstructures

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#

Physical Units

The stiffness tensor has dimensions of stress (force divided by area).
Most of the parameters used to specify material properties therefore
are stresses. They can be entered in any units you wish, as long as
you are consistent. The units you choose for stress, along with the
units you choose for length, determine the units used for forces (as,
for example, in Sections 3.27 and
3.36). The units of length are determined either by the
*height*and

*width*variables in the

*/initialize/uniform*menu (Section 3.13) or by the

*width*variable in

*PPM2OOF*.

The thickness of the elements is assumed to be 1. Forces scale linearly with the thickness.

Thermal expansion coefficients have dimensions of strain/temperature,
which is
since strain is dimensionless. The units
you use for thermal expansion must be consistent with those used
for *deltaT* (Section 3.1).

In the listings in Section 4.5 below, the dimensions of each parameter are given in brackets at the end of each description. [like this]

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