“Nitriding!” can be used to predict the distribution of nitrogen
in the nitrided layers of steel and for the visual presentation of
the calculation results. Numerical methods have been utilized to determine
the distribution of nitrogen across the nitrided layer.
This application can be an excellent teaching aid in a course of materials
science for students majoring in mechanical engineering
or material sciences. The program runs under Windows 95™.
Click here
for
DEMO
Click here
for
Polish version
Contents:
1. Overview
2. How to get more information
Overview
For any given process of steel nitriding, the program enables you to
monitor the effect of the following:
-
the diffusion saturation time on the kinetics of the diffusion layer build-up
and on the distribution of the diffusing element across the diffusion layer
-
the surface reaction rate on the thickness of the diffusion layer, on the
diffusing element's concentration at the surface of the alloy and on the
phase composition of the diffusion layer
-
the mass increase of the treated object as a function of the treatment
time
-
the temperature on the rate of the diffusion layer's growth.
The program can also be used to optimize the steel nitriding process. This
can be achieved by selecting appropriate parameter
values which will lead to the desired nitrogen concentrations throughout
the diffusion layer and a suitable phase composition of the
diffusion layer.
The following parameters are used as input for the calculations:
-
the nitrogen content in the steel, the nitrogen solubility limit in ferrite
and parameters describing the nitrogen diffusion coefficient in ferrite
(Do, Q)
-
the equilibrium concentrations of nitrogen in the gamma’ phase at the interphase
boundary ferrite/gamma’ and gamma’/epsilon, and parameters describing the
nitrogen diffusion coefficient in the gamma’ phase (Do, Q),
-
the equilibrium concentration of nitrogen in the epsilon phase at the interphase
boundary gamma’ - epsilon; maximum nitrogen concentration in the epsilon
phase, and the parameters describing the nitrogen diffusion coefficient
through the epsilon phase (Do,Q),
-
the changes in temperature, nitrogen potential of atmosphere (nitrogen
% by weight) and the atmospheric nitrogen transfer coefficient – as a function
of treatment time.
Both the data and the calculation results are displayed on the screen by
plotting the following parameters as a function of the
treatment time:
-
the temperature and the nitrogen potential of the atmosphere
-
the nitrogen concentration on the steel surface during the treatment process
-
the mass increase of nitrided objects as a function of the treatment time
-
the nitrogen distribution across the nitrided layer, subsequent to:
-
exceeding the nitrogen solubility limit in ferrite
-
creation of a stable nucleus of the gamma’ phase
-
exceeding nitrogen solubility limit in the gamma’ phase
-
creation of a stable nucleus of the epsilon phase
-
the cessation of the process
-
the thickness of individual phases in the layer: ferrite up to 0.02% N
content, and gamma and epsilon phases ( if any formed).
How to get more information
Help is available directly from the author of the application,
Dr Stanislaw
Gut.If you have any problems with
the installation, usage of the program ‘Nitriding!” or simply wish
to suggest improvements or changes you can contact the author in the following
way:
By telephone under these numbers:
Voice: +48.12.617-38-67
Voice/fax: +48.12.330-205
by e-mail: gut@uci.agh.edu.pl
or by letter at:
Stanislaw Gut
University of Mining and Metallurgy
30-059 Krakow Al. Mickiewicza 30
Poland