Optimization of process parameters in fused filament fabrication (FFF) utilizing poly lactic acid (PLA)

According to an experimental dataset under different process parameters, support vector regression (SVR) combined with particle swarm optimization (PSO) for its parameter optimization was employed to establish a mathematical model for prediction of the tensile strength of poly (lactic acid) (PLA)/graphene nanocomposites. Four variables, while graphene loading, temperature, time and speed, were employed as input variables, while tensile strength acted as output variable. Using leave-one-out cross validation test of 30 samples, the maximum absolute percentage error does not exceed 1.5%, the mean absolute percentage error (MAPE) is only 0.295% and the correlation coefficient [Formula: see text] is as high as 0.99. Compared with the results of response surface methodology (RSM) model, it is shown that the estimated errors by SVR are smaller than those achieved by RSM. It revealed that the generalization ability of SVR is superior to that of RSM model. Meanwhile, multifactor analysis is adopted for investigation on significances of each experimental factor and their influences on the tensile strength of PLA/graphene nanocomposites. This study suggests that the SVR model can provide important theoretical and practical guide to design the experiment, and control the intensity of the tensile strength of PLA/graphene nanocomposites via rational process parameters.

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Bio-composites for Fused Filament Fabrication. Effects of Maleic Anhydride Grafting on Poly(Lactic Acid) and Microcellulose

10.21203/rs.3.rs-839482/v1 ◽

2021 ◽

Author(s):

Daniele Rigotti ◽

Luca Fambri ◽

Alessandro Pegoretti

Keyword(s):

Lactic Acid ◽

Maleic Anhydride ◽

Nucleating Agent ◽

Mechanical Analysis ◽

Poly Lactic Acid ◽

Crystalline Cellulose ◽

Fused Filament Fabrication ◽

Scanning Calorimetry ◽

Electron Microscopy Analysis ◽

Reactive Mixing

Abstract Composite filaments consisting of poly(lactic acid) (PLA) and micro crystalline cellulose (MCC) were successfully used for additive manufacturing (AM) by fused filament fabrication (FFF). PLA and MCC bio-composites were obtained by direct mixing in a melt compounder; maleic anhydride (MAH) was also grafted onto PLA in reactive mixing stage to evaluate its effect on the final properties of the printed material. Filaments with various concentrations of MCC (up to a maximum content of 10 wt%) were produced with a single screw extruder and used to feed a commercial desktop FFF printer. Upon grafting of PLA with MAH, a more coherent interfacial morphology between PLA and MCC was detected by electron microscopy analysis. The thermal degradation of the PLA was unaffected by the presence of MCC and MAH. According to differential scanning calorimetry and dynamic mechanical analysis results, micro-cellulose acted as nucleating agent for PLA. In fact, the crystallization peak shifted towards lowers temperature and a synergistic effect when MCC was added to PLA grafted with MAH was observed possibly due to the increase of the chain mobility. Micro cellulose led to an increase in the stiffness of the material in both filaments and 3D printed specimen, however, a different fracture behavior was observed due to the peculiar structure of printed samples.

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Influence of Multi-Level Printing Process Parameters on 3D Printed Parts in Fused Deposition Molding of Poly(lactic) Acid Plus: A Comprehensive Investigation

American Journal of Mechanical Engineering ◽

10.12691/ajme-7-2-5 ◽

2019 ◽

Vol 7 (2) ◽

pp. 87-106 ◽

Cited By ~ 1

Author(s):

Mohammad S. Alsoufi ◽

Mohammed W. Alhazmi ◽

Dhia K. Suker ◽

Wadeea K. Hafiz ◽

Sultan S. Almalki ◽

...

Keyword(s):

Lactic Acid ◽

Process Parameters ◽

Poly Lactic Acid ◽

Comprehensive Investigation ◽

Printing Process ◽

Fused Deposition ◽

3D Printed ◽

Multi Level

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Study on the 3D printability of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(lactic acid) blends with chain extender using fused filament fabrication

Scientific Reports ◽

10.1038/s41598-020-68331-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Miguel A. Vigil Fuentes ◽

Suman Thakur ◽

Feng Wu ◽

Manjusri Misra ◽

Stefano Gregori ◽

...

Keyword(s):

Lactic Acid ◽

Chain Extender ◽

Poly Lactic Acid ◽

Fused Filament Fabrication

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Strain isolation and optimization of process parameters for bioconversion of glycerol to lactic acid

Journal of Chemical Technology & Biotechnology ◽

10.1002/jctb.2209 ◽

2009 ◽

Vol 84 (10) ◽

pp. 1576-1581 ◽

Cited By ~ 42

Author(s):

An-An Hong ◽

Ke-Ke Cheng ◽

Feng Peng ◽

Sheng Zhou ◽

Yan Sun ◽

...

Keyword(s):

Lactic Acid ◽

Process Parameters ◽

Strain Isolation ◽

Optimization Of Process Parameters

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Evaluation of the Deterioration of the Mechanical Properties of Poly(lactic acid) Structures Fabricated by a Fused Filament Fabrication 3D Printer

Inventions ◽

10.3390/inventions4010021 ◽

2019 ◽

Vol 4 (1) ◽

pp. 21 ◽

Cited By ~ 3

Author(s):

Miho Suzuki ◽

Asahi Yonezawa ◽

Kohei Takeda ◽

Akira Yamada

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

Tensile Tests ◽

Poly Lactic Acid ◽

3D Printer ◽

Fused Filament Fabrication ◽

Tensile Direction ◽

Test Pieces ◽

3D Printers ◽

Scan Pattern

A fused filament fabrication (FFF) 3D printer is a simple device capable of manufacturing three-dimensional structures in a series of easy steps. Commercial-level FFF 3D printers have spread rapidly in many fields in recent years. Poly(lactic acid) (PLA) is a biodegradable thermoplastic polymer used as a typical printing medium for FFF 3D printers. The FFF printer constructs an object with melted polymer extruded from a tiny scanning nozzle. The mechanical properties of FFF 3D structures printed with different scan patterns can therefore vary in accordance with the directions from which forces act upon them. The nozzle scan pattern also influences the deterioration of the mechanical properties of the structures in accordance with the degradation caused by the hydrolysis of PLA. In this study we conducted tensile tests to evaluate the strength characteristics of 3D printed test pieces formed from PLA using four different scan patterns: parallel, vertical, parallel-and-vertical, and cross-hatched at opposing diagonal angles to the tensile direction. We also formed test pieces by an injection molding method using the same material, for further comparison. We evaluated the deterioration of the test pieces after immersing them in saline for certain periods. After the test pieces formed by different nozzle scan patterns were immersed, they exhibited differences in the rates by which their maximum tensile stresses deteriorated and their masses increased through water uptake. The influences of the scan patterns could be classified into two types: the unidirectional scan pattern influence and bidirectional scan pattern influence. The data obtained in this research will be applied to structural design when the FFF 3D printer is employed for the fabrication of structures with PLA filament.

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