Analysis of the Surface of Parts Injected with ABS and Treated with Acetic Acid: Influence of Process Settings - Visual Computing: Scientific Visualization and Imaging Systems - page 146

Fig. 8.1 Finite element model type midplane of the specimen with the distribution channels and
residual tension curve [ 2 , 13 ]
Fig. 8.2 Determination of
thickness of electro deposited
metal layers in an ABS
injected part
Bleaching caused by the attack of the acid is an indication of the presence of
residual stress on the part surface. Electron microscopy analysis has shown
(Fig. 8.4 a and b) that wherever acid attack was present the surface presented
fissures in the shape of micro cavities.
The area attacked was observed through SEM 100 magnification. Micro cavities
showed a maximum estimated length of 110 lm and a maximum estimated width of
28 lm. Those areas with reduced residual stress were not susceptible to the attack,
thus nothing was observed through a 50 magnification (Fig. 8.4 b). Technically
speaking, this surface is not adequate for the metallization process. The part shown
in Fig. 8.3 is always used in the assembly line and due to the presence of several
grooves on the side opposite the surface indicated, the morphology of the attack
surface from a simpler part and in the shape of a specimen was chosen.