3D printing of gelatin/chitosan biodegradable hybrid hydrogel: Critical issues due to the crosslinking reaction, degradation phenomena and process parameters

In recent decades, 3D acquisition by laser scanning or digital photogrammetry has become one of the standard methods of documenting cultural heritage, because it permits one to analyze the shape, geometry, and location of any artefact without necessarily coming into contact with it. The recording of three-dimensional metrical data of an asset allows one to preserve and monitor, but also to understand and explain the history and cultural heritage shared. In essence, it constitutes a digital archive of the state of an artefact, which can be used for various purposes, be remodeled, or kept safely stored. With the introduction of 3D printing, digital data can once again take on material form and become physical objects from the corresponding mathematical models in a relatively short time and often at low cost. This possibility has led to a different consideration of the concept of virtual data, no longer necessarily linked to simple visual fruition. The importance of creating high-resolution physical copies has been reassessed in light of different types of events that increasingly threaten the protection of cultural heritage. The aim of this research is to analyze the critical issues in the production process of the replicas, focusing on potential problems in data acquisition and processing and on the accuracy of the resulting 3D printing. The metric precision of the printed model with 3D technology are fundamental for everything concerning geomatics and must be related to the same characteristics of the digital model obtained through the survey analysis.

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A multi-scale E-Jet 3D printing regulated by structured multi-physics field

Journal of Micromechanics and Microengineering ◽

10.1088/1361-6439/ac43d1 ◽

2021 ◽

Author(s):

Kai Li ◽

Yihui Zhao ◽

Maiqi Liu ◽

Xiaoying Wang ◽

Fangyuan Zhang ◽

...

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Aspect Ratio ◽

Process Parameters ◽

High Aspect Ratio ◽

Thermal Field ◽

Structural Features ◽

Microfluidic Chips ◽

Multi Scale ◽

Fluid Field

Abstract Micro/nano scale structure as important functional part have been widely used in wearable flexible sensors, gas sensors, biological tissue engineering, microfluidic chips super capacitors and so on. Here a multi-scale electrohydrodynamic jet (E-Jet) 3D printing approach regulated by structured multi-physics fields was demonstrated to generate 800 nm scale 2D geometries and high aspect ratio 3D structures. The simulation model of jetting process under resultant effect of top fluid field, middle electric field and bottom thermal field was established. And the physical mechanism and scale law of jet formation were studied. The effects of thermal field temperature, applied voltage and flow rate on the jet behaviors were studied; and the range of process parameters of stable jet was obtained. The regulation of printing parameters was used to manufacture the high resolution gradient graphics and the high aspect ratio structure with tight interlayer bonding. The structural features could be flexibly adjusted by reasonably matching the process parameters. Finally, PCL/PVP composite scaffolds with cell-scale fiber and ordered fiber spacing were printed. The proposed E-Jet printing method provides an alternative approach for the application of biopolymer materials in tissue engineering.

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On effect of chemical-assisted mechanical blending of barium titanate and graphene in PVDF for 3D printing applications

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705720945377 ◽

2020 ◽

pp. 089270572094537

Author(s):

Ravinder Sharma ◽

Rupinder Singh ◽

Ajay Batish

Keyword(s):

Mechanical Properties ◽

Barium Titanate ◽

3D Printing ◽

Comparative Study ◽

Process Parameters ◽

Processing Temperature ◽

Melt Mixing ◽

Twin Screw ◽

3D Printed ◽

The Comparative Study

The polyvinylidene difluoride + barium titanate (BaTiO3) +graphene composite (PBGC) is one of the widely explored thermoplastic matrix due to its 4D capabilities. The number of studies has been reported on the process parameters of twin-screw extruder (TSE) setup (as mechanical blending technique) for the development of PBGC in 3D printing applications. But, hitherto, little has been reported on chemical-assisted mechanical blending (CAMB) as solution mixing and melt mixing technique combination for preparation of PBGC. In this work, for preparation of PBGC feedstock filaments, CAMB has been used. Also, the effect of process parameters of TSE on the mechanical, dimensional, morphological, and thermal properties of prepared filament of PBGC have been explored followed by 3D printing. Further, a comparative study has been reported for the properties of prepared filaments with mechanically blended composites. Similarly, the mechanical properties of 3D printed parts of chemically and mechanically blended composites have been compared. The results of tensile testing for CAMB of PBGC show that the filament prepared with 15% BaTiO3 is having maximum peak strength 43.00 MPa and break strength 38.73 MPa. The optical microphotographs of the extruded filaments revealed that the samples prepared at 180°C extruder temperature and 60 r/min screw speed have minimum porosity, as compared to filaments prepared at high extruder temperature. Further, the results of the comparative study revealed that the filaments of CAMB composites show better mechanical properties as compared to the filaments of mechanically mixed composites. However, the dimensional properties were almost similar in both cases. It was also found that the CAMB composites have better properties at low processing temperature, whereas mechanically blended composites show better results at a higher temperature. While comparing 3D printed parts, tensile strength of specimens fabricated from CAMB was more than the mechanically blended PBGC.

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Functionalized poly l-lactic acid synthesis and optimization of process parameters for 3D printing of porous scaffolds via digital light processing (DLP) method

Journal of Manufacturing Processes ◽

10.1016/j.jmapro.2020.04.076 ◽

2020 ◽

Vol 56 ◽

pp. 550-561 ◽

Cited By ~ 4

Author(s):

Arvin Bagheri Saed ◽

Amir Hossein Behravesh ◽

Sadegh Hasannia ◽

Seyyed Alireza Alavinasab Ardebili ◽

Behnam Akhoundi ◽

...

Keyword(s):

Lactic Acid ◽

3D Printing ◽

Process Parameters ◽

Acid Synthesis ◽

Porous Scaffolds ◽

Digital Light Processing ◽

Optimization Of Process Parameters

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Effect of Process Parameters on Mechanical Properties of Solidified PLA Parts Fabricated by 3D Printing Process

3D Printing and Additive Manufacturing Technologies ◽

10.1007/978-981-13-0305-0_9 ◽

2018 ◽

pp. 95-104

Author(s):

Jagdish Khatwani ◽

Vineet Srivastava

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Process Parameters ◽

Printing Process

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The Impact of 3D Printing Process Parameters on the Dielectric Properties of High Permittivity Composites

Designs ◽

10.3390/designs3040050 ◽

2019 ◽

Vol 3 (4) ◽

pp. 50 ◽

Cited By ~ 2

Author(s):

Athanasios Goulas ◽

Shiyu Zhang ◽

Darren A. Cadman ◽

Jan Järveläinen ◽

Ville Mylläri ◽

...

Keyword(s):

3D Printing ◽

Process Parameters ◽

Relative Permittivity ◽

Main Process ◽

Fused Filament Fabrication ◽

Layer Height ◽

Additive Manufacturing Technology ◽

The Impact ◽

Printing Speed ◽

Hatch Spacing

Fused filament fabrication (FFF) is a well-known and greatly accessible additive manufacturing technology, that has found great use in the prototyping and manufacture of radiofrequency componentry, by using a range of composite thermoplastic materials that possess superior properties, when compared to standard materials for 3D printing. However, due to their nature and synthesis, they are often a great challenge to print successfully which in turn affects their microwave properties. Hence, determining the optimum printing strategy and settings is important to advance this area. The manufacturing study presented in this paper shows the impact of the main process parameters: printing speed, hatch spacing, layer height and material infill, during 3D printing on the relative permittivity (εr), and loss tangent (tanδ) of the resultant additively manufactured test samples. A combination of process parameters arising from this study, allowed successful 3D printing of test samples, that marked a relative permittivity of 9.06 ± 0.09 and dielectric loss of 0.032 ± 0.003.

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