Alessandro Guglielmotti

Recycling of Waste Epoxy-Polyester Powders for Foam Production

This paper proposes a new foaming technology (solid-state foaming) to produce structural foams from waste thermosetting resins. The proposed technology is easy and does not require specific and expensive equipments. Solid tablets are produced by cold compaction of resin powder, and foam by heating in an oven. Composite foams can be produced by mixing fillers and resin powder before the cold compaction. In the experiment, an epoxy-polyester (EP-PE) resin powder, deriving from the waste of a manufacturer of domestic appliances, was used with montmorillonite (MMT) particles. Resulting foams with a filler content ranging from 0 to 10 wt% were characterized in terms of physical and mechanical properties (by compression tests). Although the effect of the MMT content seems to be negative for the adopted resin, the feasibility of producing composite foams by recycling waste industrial powders is shown. The properties of the unfilled foams are sufficient for many industrial applications.

Fatigue strength of hard-chromium-plated handlebars

Prototypes of handlebars for motorcycles were fabricated by rotary bending and hard-chromium electrodeposition. Fatigue tests were carried out on rough handlebars and hard-chromium plated handlebars; the former resisted over 200.000 cycles, the latter failed at about 50.000 cycles. Scanning Electron Microscopy (SEM) allowed one to observe the presence of sub-surface cracks, which probably originated during the tube bending. Moreover numerical simulation permitted one to identify the occurrence of buckling during the bending process. The combination of buckling, cracks and residual stresses from the chromium electrodeposition results in a very poor behaviour of the handlebar under fatigue test.