The density of the part can be evaluated by two differ-
ent types of signal processing. The first alternative is to
process the image in order to obtain the contour plot by
displaying isolines. Then it can be seen from these images
that the lower the density of the sample is, the more
changes the image has. This is due to the fact that when
the material porosity increases, that makes the ultrasonic
waves go through much more reflections. The second alter-
native is to process signal data in order to evaluate the
material attenuation which is related to the density. The
lower the density, the higher the attenuation.