Experimental investigation on the flow properties of sand granules in the process of sand mold printing

Abstract

Purpose This paper aims to determine how the viscosity and curing agent content affect the flowability of moist silica sand granules. In addition, a coating device was designed according to the flow properties of silica sand granules. Design/methodology/approach The flowability of silica sand granules premixed with two curing agents of different viscosities is studied using a Jenike shear apparatus. An open-ended device was used in discharge testing of sand granules with a design based on the variable dip angle of the two plates and variable outlet size. Findings The test results show that increasing the curing agent content would significantly decrease the flowability of silica sand granules, and a curing agent of higher viscosity has a greater effect on the flowability of silica sand. The presence of a curing agent strengthens the cohesion among sand granules, lubricates them and restrains their deformation. The shape function of the coating device was obtained by theoretical derivation. Practical implications The flow properties provide a valuable theoretical guidance for the design of coating device for sand mold printing. Originality/value This paper deals with experimental work on flow properties of silica sand granules with different viscosities and curing agent content. The shape function of a wedge-shaped coating device is obtained based on experimental data.