Calculation of Diffraction Elastic
Constants
What is ISODEC?
ISODEC is a program for the calculation of diffraction elastic
constants (DEC). DEC are used to convert lattice
strain measured by diffraction into macroscopic stress. It can also calculate
stress from measured d-spacings and vice versa. In the case of materials with
preferred orientation it reads the crystallite orientation distribution
function (ODF – must be supplied by the user) in textual form as output
from free texture software (popla and MTEX). Program
functions that use the ODF are: pole figure calculation, intensity fractions of
overlapped reflections, and DEC (stress factors).
What operating system is
required?
The executable is a Windows program. However, I have had no
problems in running IsoDEC under MacOSX
and x86 linux using either Darwine
(MacOSX) or Wine as Windows emulators.
What does the installation package include?
The installation is very basic. Unzip the IsoDEC.zip file in
a directory of your choice and run IsoDEC.exe from there. The file pfcryst.dat
contains single crystal elastic constants of some common materials and it
should be in the same directory as IsoDEC. There is a
basic help file (IsoDEC.pdf) and several examples consisting mainly of ODFs
that were generated by popla (extension *.SHD, *.SOD
or *.COD) or by MTEX (extension *.txt).
Will the source code be
made available?
Maybe later.
ISODEC was written in Pascal/Delphi, and there is a good chunk of code in IsoDEC that was written using Numerical Recipes in Pascal by W. Press et al. So there are
copyright issues and it cannot be simply made available until those code
sections are replaced by public domain code. Also, the code is not very well
documented.
Who maintains IsoDEC?
That would be me (Thomas Gnäupel-Herold:
tg-h@nist.gov). All questions, and
especially inconsistencies or bugs that are discovered using IsoDEC should be directed to me. As I am using it quite
often I am naturally very interested in finding out about problems with IsoDEC. Suggestions about missing features are also
welcome.
Download
IsoDEC
can be downloaded here.
BT8.
Updates
IsoDEC
is currently updated to include better handling of calculations for multiphase
materials. Please check back soon!
Neither the author nor the
U.S. Government makes any warranty, expressed or implied, or assumes any
liability or responsibility for the use of this information or the software
described here. Brand names cited here are used for identification purposes and
do not constitute an endorsement by NIST.
Last
modified 25-January-2012