Additive manufactured 3Y‐TZP ceramics: Study of micromechanical behavior by nanoindentation and microscratch method

Abstract

The mechanical property of advanced ceramics by additive manufacturing through layer-by-layer processing and subsequent sintering has been employed as a key basis for optimizing the processing and developing future application. 3Y-TZP ceramic was fabricated by stereolithography-based additive manufacturing, and the mechanical properties were investigated by nanoindentation and microscratch testing. The microscopic mechanism and evolution of surface deformation and damage induced by scratching were revealed by scanning electron microscopy and surface interferometer. Results showed that the nanoindentation hardness and elastic modulus were comparable to those of conventional process. With the increase in the applied normal load, the scratch-induced damage followed three sequential stages, that is, plastic plowing, microcracking and surface spalling. The magnitude of the microcracks nucleated during scratching depended on the applied normal load. Concerning the homogeneity and integrity with the sintered parts without delaminated cracks and pores, the evolution of surface damage was discussed in different stages. It was concluded that the layer-by-layer process did not affect the characteristic of microcracking evolution. K E Y W O R D S3Y-TZP, additive manufacturing, micro-scratch test, nanoindentation, stereolithography

Hot ceramic lithography of silica-based ceramic cores: The effect of process temperature on vat-photopolymierisation

“…The average particle size, PSD, and the particles shape are critical factors in VPP printing, as they highly impact the viscosity of the slurry, and its stability and homogeneity, as well as the precision of the cores after the sintering process (due to the residual stress in the printed component caused by peeling forces, which are associated with the mixtures viscosities). The recommended average particle size for most VPP applications are ranged from 100 to 500 nm to achieve higher reactivity for sintering, resulting in better mechanical properties [44][45][46][47][48][49][50][51][52][53]. Generally, the narrow PSD is preferred to print fine and smooth surfaces [54], and the spherically shaped synthesised nan/micro particles (with a low aspect ratio) increase the effective maximum solid loading, subsequently lowering the viscosity compared to coarse particles [55].…”

3Y-TZP DLP Additive Manufacturing: Solvent-free Slurry Development and Characterization

“…The monomer 1,6-hexanediol diacrylate (HDDA) has been used in the vast majority of such work due to its low viscosity and its ability to form crosslinked organic networks 18 . HDDA has been used in association with other monomers such as ethoxylated pentaerythritol tetraacrylate (EPTA) 19,20 , polyethylene glycol diacrylate PEGDA 17 , ethoxylated pentaerythritol tetraacrylate (PPTTA) [21][22][23] , and 1,1,1-Trimethylol propane triacrylate (TMPTA) 4, 24,25 , or as a single monomer [26][27][28] . Moreover, an appropriate photoinitiator must be chosen to initiate the photopolymerization reactions, considering mainly its compatibility with the adopted monomers and the relationship between its light absorption spectrum and the wavelength emitted by the light source 29,30 .…”

Additive manufacturing of advanced ceramics by digital light processing: equipment, slurry, and 3D printing

“…On the other hand, fine particles are more reactive than larger ones during sintering, which results in denser parts with better mechanical properties [23,132,174]. Therefore, the average of the particles in ceramic slurries for additive manufacture usually ranges between 90 and 500 nm [4,8,129,130,143,146,156,158,[175][176][177][178]28,179,180,33,36,37,66,76,107,128].…”

“…Several types of materials have been used as dispersants in formulations for vat photopolymerization based on non-polar acrylates, including several commercial hyperdispersants, which have at least one hydrophilic anchor group and one hydrophobic polymeric chain [213]. Although their chemical structure is not publicly available, the anchors are commonly functional groups of high polarity, such as amine [25,27,159,180,190,193,33,107,131,133,142,147,151,156], carboxyl [8,28,30,131,170,189,193], silane [64,131,140,143,188] and phosphoric acid/oxide [151,158,195,196]. Table 6 shows a summary of dispersants reported in the literature that have yielded good results.…”

“…Salt of unsaturated polyamine amides and lowmolecular acidic polyesters [180] BYK-w 969 (BYK-Chemie)…”