Investigation of process parameter effect on anisotropic properties of 3D printed sand molds

Abstract

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.

On the rapid manufacturing process of functional 3D printed sand molds

“…The recommended process parameters for minimal variation in 3PB strength and permeability along the job-box were selected according to Ref. [9,10,44] and are listed in Table 1. The recoating speed was kept constant throughout the printing process and only the printing resolution (furan drop spacing) was altered to achieve different binder percentages.…”

“…Among the available AM techniques, the powder-based ink-jet 3D printing, which is based on the basis of a chemical reaction between silica sand powder and an acidic binder, is widely used to manufacture sand molds. An extensive literature review in this area of research [8] and a few studies on the relationship between the properties of the 3D printed specimen and processing parameters [9,10] have been recently published.…”

“…The same aspects were also studied in the case of an ExOne TM 3D printer, finding that the specimens had high mechanical strength (~1.3 MPa) with less amount of binder than in ZCAST system, due to the well-controlled distribution of silica sand and furan resin binder [23]. Recommendations on the orientation and position of the samples in the job box can also be found in the recent literature in order to minimize the anisotropic behavior of the molds produced with this technology [9].…”

Study of the evolution of transport properties induced by additive processing sand mold using X-ray computed tomography

“…The porosity values measured from experiments were close to 49-51% for all printed specimens, with a standard deviation of 0.25%. Also, the permeability of the 3DP sand mold samples was determined with a permeameter device (Simpson-Electrical), following the recommendations of the American Foundry Society (AFS) and the same procedure presented in previous works by (Coniglio et al, 2017), (Sivarupan et al, 2017), (Mitra et al, 2018) and (Mitra et al, 2019). Therefore the entire procedure for the permeability experiment will not be presented here.…”

“…Also, various 3D printing process parameters directly affect the quality of the sand mold. In particular, the relationship between the printing process parameters (print position/orientation in job-box, recoater speed, and print resolution) and their influence on the properties of the 3DP sand mold have been extensively investigated in previous works using both mathematical modelling by (Coniglio et al, 2017) and experimental validations by (Sivarupan et al, 2017). (Sivarupan et al, 2017) showed how the printing processing parameters affected mechanical properties in 3DP sand mold.…”