Effects of printing parameters on the mechanical properties of sand molds produced by a novel binder jetting 3D printer

Abstract

Technological developments have an effect on the field of manufacturing and many other fields. In recent years, the importance of additive manufacturing in the casting industry has increased. The production of especially reverse angled complex shaped parts, which are very difficult to produce with traditional casting methods, is easier and more economical thanks to the additive manufacturing method by pressing sand molds and casting. One of the additive manufacturing methods commonly used for sand mold production is the binder jetting 3D printing method. In this research, a novel binder jetting 3D printer with a new spray-nozzle system was designed and produced that differs from traditional inkjet technology. Sand molds were produced with three different printing parameters: printhead feed rate, catalyst ratio, and sand grain size using silica sand, furan resin and catalyst. To determine the mechanical and microstructure properties of the produced sand molds, porosity, three-point bending, dimensional tolerance, and scanning electron microscopy analysis were performed. According to the test results, the porosity ratios of the samples were found to be in the range of 38.69%& horbar;56.65%, the maximum flexural strength was in the range of 0.0301 MPa & horbar;0.3844 MPa. In the cylindrical sample, the best value for dimensional tolerance for diameter measurement was 0.6 mm nominal deviation, and the best value for height was 0.3 mm nominal deviation. As a result, the samples produced according to the test results were generally usable as sand molds.