Publication:
3D printing of high solid loading zirconia feedstock via screw-based material extrusion

Date
2023
Authors
Lim I.Y.
Ting C.H.
Ng C.K.
Tey J.Y.
Yeo W.H.
S R.
Lee K.Y.S.
Chuah Y.D.
Teng W.D.
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier Ltd
Research Projects
Organizational Units
Journal Issue
Abstract
Zirconia ceramic (3Y-TZP) feedstocks with solid loadings from 50 vol% to 68 vol%, in a 60:40 paraffin wax to LDPE ratio binder system, were prepared and printed using a screw-based material extrusion printer. A two-step debinding process involving solvent debinding (cyclohexane + ethanol) and thermal debinding (140 �C�600 �C at 0.2 �C/min) followed by sintering at 1500 �C for 2 h was employed. Tests performed include TGA, density test, Vickers hardness and fracture toughness, XRD, and SEM. The TGA result showed two significant drops in weight starting at 180 �C and 380 �C, which corresponds to the decomposition of paraffin wax and LDPE, respectively. A minimum of 40 wt% of soluble binder was removed from the green sample after solvent immersion for 3 h at 40 �C for solid loadings ?55 vol%. High solid loading feedstocks produced samples with comparable density, Vickers hardness and fracture toughness, which are 97.5%, ?12.3 GPa, and ?5.5 MPa m1/2, respectively
while XRD and SEM shows no adverse tetragonal to monoclinic phase transformation and grain growth, respectively. This study demonstrates that 3D printing of granular 3Y-TZP ceramic feedstock via screw-based material extrusion technique is feasible even with high solid loadings, which is usually difficult to fabricate into flexible filaments and print due to high viscosity. � 2023 Elsevier Ltd and Techna Group S.r.l.
Description
Keywords
Additive manufacturing , Debinding defects , Mechanical properties , ZrO<sub>2</sub> feedstock , 3D printing , Ductile fracture , Extrusion , Fracture toughness , Grain growth , Organic solvents , Paraffins , Screws , Sintering , Vickers hardness , X ray diffraction , Zirconia , 3-D printing , 3D-printing , Debinding , Debinding defect , High solid loading , Solid loading , Vicker hardness , XRD , Zirconia ceramic , ZrO2 feedstock , Feedstocks
Citation
Collections