Papers by Author: Mario Fafard

Abstract: The current study investigates the effects of mixing parameters on the quality of anode paste and green anode used in aluminum electrolysis. Four mixing times and four mixing temperatures were applied to prepare anode pastes using calcined petroleum coke and coal tar pitch, as raw materials. The volume of the pores in the paste was used as the indicator for mixing effectiveness. A compression test was applied to the pastes to study the compactability of these pastes and to investigate the effect of mixing parameters on density of the green samples. It was shown that mixing parameters influence the size, volume and surface area of paste porosity and also its compaction behaviour.

Abstract: Tubular products have very important applications in various areas especially in the transportation industries. For instance, in the structure of cars there are various tubular products like roof headers, engine cradles, roof rails and frame rails with complex geometries which most of them need multiple steps like tube drawing, tube bending and hydroforming for their production. Based on the recent studies by this group, it was proven that in most of the structural tubular parts in the cars it was not necessary to have constant thickness along the axial direction of tube and it will be considered as overdesign and the overall weight of structures can be reduced considerably by using variable thickness tubes. In this paper, the variable thickness tube drawing and its applications in the tube bending and hydroforming applications were studied. The results showed that this process can have important role in reduction of defective parts in the production of complex tubes by the tube hydroforming method. However especial considerations should be taken into account in the design of thickness distribution along axial direction of these kinds of tubes to avoid problems in the drawing step and as well in the bending and hydroforming steps.