Investigating the effect of mold surface roughness in thin-wall micro injection molding

The large surface area to volume ratio that characterized the micro injection molding process makes interfacial phenomena particularly critical and fundamental for the overall effectiveness of the process. This is more evident for micro injection molding of thinner part, where the roughness is comparable to at least one between the overall dimensions of the cavity. In this case, the contact situation between polymer and mold, significantly affects the heat transfer at interface, which strongly influences the polymer flow behavior. Therefore, in this paper, the effects of the polymer-tool interface on polymer flow were investigated. In particular, the filling of a representative micro part with a thickness of 100 ?m was studied as a function of surface roughness and mold wettability