A study on topology optimization and cost estimation of fused depostion modelling parts

Abstract: Additive manufacturing (AM) is acquiring a lot of importance in the manufacturing field. It makes the whole manufacturing process easier and effectively brings down the manufacturing cost compared to the traditional methods. It also provides the manufacturer with the freedom of customization according to each customer. In addition, the implementation of Topology Design Optimization helps in further reduction of costs by reducing the material consumption and energy needed to manufacture the product. In this thesis, products of TylöHelo AB, a leading manufacturer of sauna and steam are studied and optimized. TylöHelo products are manufactured using injection molding methods, in this process, molds are prepared initially, and later molten plastics are shaped using these molds. Molds are expensive and hard to manufacture too. In these types of techniques, the rate of manufacturing is high, but customization is very hard for each new type of design. A new mold has to be printed for each new design. Due to the high cost of mold designing and manufacturing, customization is very rarely seen. In this thesis, a certain product of TylöHelo sauna assembly is selected and redesigned using Topology Optimization to achieve both reduced manufacturing cost and good mechanical properties without compromising on the functional behavior. Solid mechanics simulation is performed to assess the mechanical properties of the part optimized and is compared to the original part. Furthermore, Fused Deposition Modeling (FDM), an extrusion-based AM, is used for fabricating the part and then implemented in the assembly of the sauna room. Finally, a detailed cost analysis is presented to provide an estimation of savings incurred for the company. This thesis identified two new topology optimized design based on manual methods and using the software. The results show that the new designs had nearly 58 to 67% cost reduction compared to the original 3D printed design and 64-69% reduction in mass of the product. This also means that the 3D printed topology optimized part can match the prices set by the injection molding. However, the 3D printed part quality and high-volume production can still be a challenge. This thesis also provides a guideline for the redesign manufactures, trying to incorporate Additive manufacturing in their production line.