Numerical evaluation of ABS parts fabricated by fused deposition modeling and vapor smoothing

The automotive industry has focused to use polymer materials in order to increase energy efficiency.So, the industry pays attention to use 3D printing technologies using several polymers.Among several 3D printer technologies, fused deposition modeling (FDM) is one of the popular 3D printing technologies due to an inexpensive extrusion machine and multimaterial printing.FDM could use thermoplastics such as ABS, PLA, ULTEM so on.However, it has a problem related to the post-processing because FDM has relatively poor layer resolution.In this study, the mechanical properties of ABS parts fabricated by FDM were measured.The ABS parts were divided into one with vapor smoothing process and the other without the vapor smoothing process which is one of the post-processing methods.Using dynamic mechanical analysis (DMA) and dilatometer, temperature-dependent storage modulus and CTE for ABS specimens were measured.Based on the measured thermo-mechanical properties of ABS parts, finite element analysis was performed for an automotive bumper made of ABS.Moreover, response surface methodology was applied to study relationships among design parameters of thickness of the bumper, ambient temperature, and application of the vapor smoothing process.In result, a design guideline for a ABS product could be provided without time-consuming experiments