Effects of process parameters on surface roughness in saw cutting of polypropylene/TiO2 nano composites


JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING, vol.36, no.3, pp.615-621, 2014 (SCI-Expanded) identifier identifier


Polymer matrix nano composite parts filled with inorganic particles are obtained by primary processes such as hot pressing, extrusion or plastic injection. Saw cutting and drilling are generally used as secondary processes in final shaping of these polymer composite parts. In this study, the effects of cutting speed, feed rate, saw pitch, and inorganic particle content on the surface roughness of the cut workpiece were investigated in saw cutting of polypropylene (PP)/TiO2 nano composites. Polymer composites were obtained by melt mixing of PP and TiO2 with a twin screw extruder under different nano particle loadings. Silane was used as a dispersant. Polymer composite parts were obtained by plastic injection molding and prior to saw cutting. Mechanical tests and morphological observations were made for characterizing the materials. In saw cutting of the parts, the parameter design was done by Taguchi method. Saw pitch, feed rate, cutting speed, and TiO2 particle contents were selected as factors. Feed rate was found to be the most effective parameter on the surface roughness of the cut workpiece followed by cutting speed, nano particle concentration and saw pitch.