Effect of Hot Vapor Smoothing Process on Surface Hardness of Fused Deposition Modeling Parts

Fused deposition modeling (FDM) has a staircase effect (as inherent process characteristics), which results in rough surface of the final components (usually of polymer-based materials such as acrylonitrile butadiene styrene [ABS]). This is one of the major limitations of this process, which hinders the use of this technique in precision industrial applications such as assembly parts and investment casting. Hot vapor smoothing (HVS) is one of the commercial techniques available for the improvement of surface finish of the FDM-based components. However, the reflow of the material by application of HVS may affect the surface hardness, tensile strength, and other mechanical properties of ABS parts. In the present study, surface hardness of ABS components has been improved through the HVS process by using acetone as smoothening media. Parts with different shapes and at different densities of FDM system were prepared at 0 degrees orientation. Design of experimentation has been employed for optimization of input process parameters (namely geometry of the components/appliance, density of components/appliance, and acetone exposure time) in response to surface hardness of the parts. The scanning electron microscopic-based characterization of the components was carried out for justification of the surface hardness data.