This paper presents results of a research on the possibilities of applying 3D printed casting models for small production series as alternative to traditional tooling production on automated DisaMatch mould production lines. The main task was to verify and compare the dimensions of the 3D printed models before and after moulding process. The paper discusses main advantages and disadvantages of the 3D printing methods used like FDM (Fused Deposition Modeling)/FFF (Fused Filament Fabrication), SLA (stereolitography) and DPP (Daylight Polymer Printing). Measurement of casting model outside dimension change resulting from moulding sand friction on their surface was made with the use of GOM INSPECT software on the basis of 3D scans made with ATOS TripleScan optical scanner. Hardness of 3D printed models made of ABS, Z-ULTRAT, three different photopolymer resins (from FormLab and Liquid Crystal companies) was verified. The result of the research printed models usability for the foundry industry was presented.
3D printing in FDM (Fused Deposition Modelling) technology is commonly used, mainly in the preparation of prototypes, but also for the production of ready-made elements. Objects printed using the FDM method have characteristic, adverse surface features related to the limitations of this technology. That is why surface treatment of 3D prints becomes crucial. One of the method is metal plating of elements. The most frequently used material in FDM technology is PLA (polylactic acid) and ABS (acrylonitrile butadiene styrene). Study of surface parameters determination for ABS prints after galvanic copper plating is presented in this paper. For this purpose, samples printed with ABS were smoothed in acetone vapour. Most favorable parameters of the surface were obtained for samples that had contact with acetone vapour for 60 minutes. Ultimately, surface analysis of samples after graphite coating and subjected to copper plating was performed. It was found that surface parameters are close to results obtained with traditional methods of metal processing.
In sand casting, Fused Deposition Modeling (FDM) printing by using Poly Lactic Acid (PLA) filament is one of the innovative foundry technologies being adopted to substitute traditional pattern making. Several literatures have reported the influence of process parameters such as raster angle and print speed on some mechanical properties of FDM-printed, PLA-prototypes used in other applications. This study investigated the effects of interior fill, top solid layer, and layer height on the compressive strength of rapid patterns for sand casting application. Different values of the process parameters were used to print the pre-defined samples of the PLA-specimens and a compression test was performed on them. The coupled effects of the process parameters on compressive strength were investigated and the optimum values were determined. Interior fill of 36%, layer height of 0.21 mm and top solid layer of 4 were found to produce a FDM-printed, PLApattern that sustained a compaction pressure of 0.61 MPa. A simulation analysis with ANSYS® to compare failure modes of both experiment and model shows a similarity of buckling failure that occurred close to the base of each specimen.