Mathematical Approach to Find Warpage Deformation of FDM Build Parts

Abstract

Rapid Prototyping is a type of Additive Manufacturing (AM) process, which deals with the fast manufacturing of parts. Fused Deposition Modeling (FDM) is one of the most appreciated AM process, which uses thermoplastic material as filament feed. The part quality, durability and mechanical strength also gets severely affected because of the undesirable effect taking place during the part fabrication process. It is already known that the FDM works on layer by layer mechanism and the heated nozzle extrudes the semi-molten thermoplastic filament at a high temperature. So during the fabrication of each layer, there is a working mechanism of forced convection due to the non-uniform cooling of the deposited layer, between the semi-molten hot material and the chamber temperature. This may sometime leads to shrinkage and warps deformation in the built parts. Minimization of these issues can result in better part accuracy, strength and quality as well. Here in this paper four input process parameters are considered such as Raster Width, Raster Angle, Layer Thickness and Air Gap, and their effects on warpage deformation are calculated mathematically using MATLAB R2017a. Design of Experiments (DOE) approach is made to get experimental sets. ANOVA is used to analyze the significance of each parameter on warpage. Response Surface Methodology (RSM) technology is used to generate the response plots. The regression equation for the total number of lines establishing a relation between process parameters and the response is generated.