Factors Influencing the Mechanical Properties of Three-Dimensional Printed Products From Magnesium-Potassium-Phosphate Cement Material (2019-02)¶

A three-dimensional powder printer was developed and installed, and the specimens were successfully printed at a maximum compression strength of 19.4 MPa at the age of 28 days, with magnesium potassium phosphate cement (MKPC) as the raw material. The printing process makes a sandwich-like structure from a group of MKPC sticks, with an average diameter of 1 mm and printed side-by-side to form a layer and then continuous layers to make a 3D object, by jetting water to the premixed powder of ball-milled magnesium oxide and potassium di-hydrogen phosphate instead of mixing water together with the powder at the same time. Preliminary mechanical test results show obvious distinctive, when the samples loaded in X,Y,Z directions, due to the main mechanical contribution from the MKPC sticks, followed by the bonding of neighbor sticks, and, finally, the layer joint bonding. The joint space of the neighbor sticks and layers have been further studied to analyze the mechanical properties of the final printed result to verify that the layer thickness and the stick/layer combination degree is the key factor to the mechanical properties of the 3D printed result.