Once temperature has been computed,
*CrysMAS* can compute the von Mises stress and other stress coefficients. Prerequisite is that stress constants have been specified for the material of the sample.

The following tutorial task exemplifies the procedure:

The stress-strain relationship for a Thermoelastic anisotropic solid body in cylindrical coordinates and for the axisymmetrical case is defined as follows:

α = Thermal expansion coefficient

T

_{ref}= Reference temperature for the relaxed bodyε

_{rr}, ε_{ φ φ }, ε_{zz}, ε_{rz}= Strain components¯C

_{ij}= Elastic material constants in the Voigt notation. Their dependence on the crystallographic orientation with respect to the cylindrical axis, i.e. the growth direction <111> or <100> and how to respect anisotropic effects is described in more details in the paper of J. C. Lambropoulos, see*Bibliography*.

To take into account the anisotropy of the material the
elastic constants ¯C_{ij} will be
calculated as given by Lambropoulos.

An important scalar for the discussion of stress in solid bodies, especially for
crystal growth, is the von Mises Stress
σ
_{Mises}, which is computed from the distinct stress components.
In cylindrical coordinates it is defined as:

Further details can be found in M. Kurz, Development of CrysMAS, 1998, see
*Bibliography
*.