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FDM approach to build defect-free and intricate shapes of 3D printed ZrO2 based PLA composites.

The investigation underline the in situ formation of ZrO

A series of zirconia toughened alumina (ZTA) system with varied concentrations of Yb3+ substitution were synthesized. The influence of Yb3+ at the resultant crystal structure, morphological, mechanical, optical and computed tomography features were evaluated. 20 mol. % Yb3+ substitution facilitated tetragonal ZrO2 (t-ZrO2) stabilization while polymorphic t-ZrO2 to cubic ZrO2 (c-ZrO2) transition is witnessed beyond this limit until to attain the solubility limit of 50 mol. %. Excess Yb3+ beyond the substitution limit prefers to react with Al2O3 to yield Yb3Al5O12. Optical analysis showcase the typical emission behavior of Yb3+; nevertheless, the t- → c-ZrO2 polymorphic transition annulled this characteristic emission. Morphological analysis revealed the existence of two different crystalline phases pertinent to ZrO2 and Al2O3. Hardness and Young’s modulus determined from the indentation ensured better results that are consistent with the commercial ZTA implants. Further CT imaging potential of Yb3+ substituted ZTA is verified from the experimental results.

The investigation underline the in situ formation of ZrO2/ZnFe2O4 composites and the resultant structural, morphological, mechanical and magnetic properties. The characterization results ensured the crystallization of tetragonal ZrO2 (t-ZrO2) and ZnFe2O4 phases at 900 °C. Depending on Zn2+/Fe3+ content, the composite system revealed a gradual increment in the phase yield of ZnFe2O4. The significance of monoclinic ZrO2 (m-ZrO2) is also evident in all the systems at 900 °C; however, the incremental heat treatment to 1300 °C indicated its corresponding loss, thus indicating the reverse m- → t-ZrO2 transition. The crystallization of ZnFe2O4 as a secondary phase in the t-ZrO2 matrix is also affirmed from the morphological analysis. Mechanical studies accomplished good uniformity in all the investigated compositions despite the variation in the phase content of ZnFe2O4 in composite system. All the t-ZrO2/ZnFe2O4 composites ensured strong ferrimagnetic features and moreover better biocompatibility and non-toxicity characteristics were displayed from in vitro tests.