Sights Inside the Virtual Engineering Education - Web-Based Engineering Education: Critical Design and Effective Tools - page 168

Figure 6. Employing a system of software to present a virtual reality

pores in order to predict the fatigue life or to
induce special morphology distribution of pores
during the producing process and to control the
mechanical properties. To get closer to the natural
morphology of the pores, now the researchers are
more interested in three dimensional characteriza-
tions of pores which present the actual shape and
volume of the pores.
Computed tomography (CT) is a technique to
identify the volumetric distribution of the “den-
sity” of the material, describing the pores three
dimensionally. CT is a precise digital geometry
process able to generate three dimensional vol-
umes of the inside of an object using a large series
of two dimensional images and joining them
together. The information held in the volumetric
pixel, the voxel, is the absorption coefficient of
the material, which is somehow related to the
density of the material itself.
The student may be interested in the three-
dimensional description of a pore, starting from
the volumetric information of a specimen portion.
This is useful to understand the real shape of a
complex phenomenon that can be for example the
casting of metal materials, and it may be also use-
ful for a subsequent finite element analysis based
on real morphology and not an approximation.
In Figure 7a it is possible to see the distribu-
tion of pores inside a small cylindrical specimen

of 4mm diameter this model has been made in
3D-Pores using the measured data of 3D X-ray.
Figure 7b is a typical portion of cross-section of
such a specimen. However the 2D pore cross-
section would not help the student to understand
the correct shape as the real three-dimensional
reconstruction. The three-dimensional pore shown
in Figure 8 is an example of a real pore recon-
structed by 3D-Pores.
The other example which is related to several
deviations of engineering is measuring the mate-
rial properties and mechanical behaviors. These
are usually the main subject of many engineering
courses. In addition to many theoretical lessons,
the students have to make the experiments in
laboratory and gain a deep understanding of dif-
ferent properties and different behaviors.
Experiment design, making the measurements,
collecting the data, statistical investigation and
interpretation of data are different part of real
experiments that is more productive if are done
by the students themselves rather than being based
on just the theoretical sessions.
Many mechanical processes are strain-driven,
thus it is very important to understand its behavior
due to loading. In order to experience differ-
ent approaches to strain measurements, there
are different devices used to help the students
to understand the meaning of deformation and