There are many 3D printing technologies available, and each technology has its strength and weakness. The 3D printing of sand moulds, by binder jetting technology for rapid casting, plays a vital role in providing a better value for the more than 5000 years old casting industry by producing quality and economic sand moulds. The parts of the mould assembly can be manufactured by precisely controlling the process parameters and the gas producible materials within the printed mould. A functional mould can be manufactured with the required gas permeability, strength, and heat absorption characteristics, and hence the process ensures a high success rate of quality castings with an optimised design for weight reduction. It overcomes many of the limitations in traditional mould design with a very limited number of parts in the mould assembly. A variety of powders, of different particle size or shape, and bonding materials can be used to change the thermal and physical properties of the mould and hence provide possibilities for casting a broad range of alloys. Limited studies have been carried out to understand the relationship between the characteristics of the printed mould, the materials used, and the processing parameters for making the mould. These deficiencies need to be addressed to support the numerical simulation of a designed part, to optimise the success rate and for economic as well as environmental reasons. Commonly used binders in this process, e.g. furan resins, are carcinogenic or hazardous, and hence there is a vital need for developing new or improved bonding materials.Contents * Corresponding author.

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is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. ABSTRACTThe development of sand mold three-dimensional printing technologies enables the manufacturing of molds without the use of a physical model. However, the effects of the three-dimensional printing process parameters on the mold permeability and strength are not well known, leading the industries to keep old settings until castings have recurring defects. In the present work, the influence of these parameters was experimentally investigated to understand their effect on the mold strength and permeability. Cylindrical and bar-shaped test specimens were printed to perform respectively permeability and bending strength measurements. Experiments were designed to statistically quantify the individual and combined effect of these process parameters. While the binder quantity only affects the mold strength, increasing the recoater speed leads to both greater permeability and reduced strength due to the reduced sand compaction. Recommendations for optimizing some 3D printer settings are proposed to attain predefined mold properties and minimize the anisotropic behavior of the sand mold in regards to both the orientation and the position in the job box.