Fused deposition modeling(FDM)has unique advantages in the rapid prototyping of thermoplastics which have been developed in diverse fields.However,although great efforts have been made to optimize FDM process,the mech...Fused deposition modeling(FDM)has unique advantages in the rapid prototyping of thermoplastics which have been developed in diverse fields.However,although great efforts have been made to optimize FDM process,the mechanical properties of printed parts are limited by the weak interlamination bonding as well as the poor performance of raw filaments used,such as acrylonitrile butadiene styrene(ABS),polylactic acid(PLA).Adding fibers into thermoplastic matrix and preparing high-performance filaments have been indicated to enhance the properties of fabricated parts.Recently,heat-resistant polyetheretherketone(PEEK)and its fiber reinforced composites were proposed for FDM process due to overcoming the limitation of equipment and process.However,few researches have been reported on the effects of FDM-3 D printing parameters on the mechanical properties of fiber reinforced PEEK composites.Therefore,5 wt%carbon fiber(CF)and glass fiber(GF)reinforced PEEK composite filaments were prepared respectively in this study.The effects of various printing parameters including nozzle temperature,platform temperature,printing speed and layer thickness on the mechanical properties(including tensile strength,flexural strength and impact strength)were surveyed.To analyze the microstructure and failure reasons of printed CF/PEEK and GF/PEEK samples,the tensile fractured surfaces were investigated via scanning electron microscope(SEM).展开更多
Material extrusion additive manufacturing has rapidly grown in use for tissue engineering research since its adoption in the year 2000. It has enabled researchers to produce scaffolds with intricate porous geometries ...Material extrusion additive manufacturing has rapidly grown in use for tissue engineering research since its adoption in the year 2000. It has enabled researchers to produce scaffolds with intricate porous geometries that were not feasible with traditional manufacturing processes. Researchers can control the structural geometry through a wide range of customisable printing parameters and design choices including material, print path, temperature, and many other process parameters. Currently, the impact of these choices is not fully understood. This review focuses on how the position and orientation of extruded filaments, which sometimes referred to as the print path, lay-down pattern, or simply'scaffold design', affect scaffold properties and biological performance. By analysing trends across multiple studies, new understanding was developed on how filament position affects mechanical properties. Biological performance was also found to be affected by filament position, but a lack of consensus between studies indicates a need for further research and understanding. In most research studies, scaffold design was dictated by capabilities of additive manufacturing software rather than free-form design of structural geometry optimised for biological requirements. There is scope for much greater application of engineering innovation to additive manufacture novel geometries. To achieve this, better understanding of biological requirements is needed to enable the effective specification of ideal scaffold geometries.展开更多
The influence of processing parameters on the precision of parts fabricated by fused deposition modeling （FDM） technology is studied based on a series of performed experiments. Processing parameters of FDM in terms ...The influence of processing parameters on the precision of parts fabricated by fused deposition modeling （FDM） technology is studied based on a series of performed experiments. Processing parameters of FDM in terms of wire-width compensation, extrusion velocity, filing velocity, and layer thickness are chosen as the control fac- tors. Robust design analysis and multi-index fuzzy comprehensive assessment method are used to obtain the opti- mal parameters. Results show that the influencing degrees of these four factors on the precision of as-processed parts are different. The optimizations of individual parameters and their combined effects are of the same impor- tance for a high precision manufacturing.展开更多
Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requireme...Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requirements of high service temperature,high conductivity and high resolution remains a challenge.In this paper,a hybrid AM method combining the fused deposition modeling(FDM)and hydrophobic treatment assisted laser activation metallization(LAM)was proposed for manufacturing the polyetheretherketone(PEEK)-based 3D electronics,by which the conformal copper patterns were deposited on the 3D-printed PEEK parts,and the adhesion between them reached the 5B high level.Moreover,the 3D components could support the thermal cycling test from-55℃ to 125℃ for more than 100 cycles.Particularly,the application of a hydrophobic coating on the FDM-printed PEEK before LAM can promote an ideal catalytic selectivity on its surface,not affected by the inevitable printing borders and pores in the FDM-printed parts,then making the resolution of the electroless plated copper lines improved significantly.In consequence,Cu lines with width and spacing of only60μm and 100μm were obtained on both as-printed and after-polished PEEK substrates.Finally,the potential of this technique to fabricate 3D conformal electronics was demonstrated.展开更多
Based on analyzing the influences of a slicing scheme on stair-stepping effect, supporting structure, efficiency and deformation, etc. , analytical hierarchical process （AHP） combining with fuzzy synthetic evaluatio...Based on analyzing the influences of a slicing scheme on stair-stepping effect, supporting structure, efficiency and deformation, etc. , analytical hierarchical process （AHP） combining with fuzzy synthetic evaluation is introduced to make decision in slicing schemes for a processing part. The application in determining the slicing scheme for a computer mouse during prototyping shows that the method increases the rationality during decision- making and improves quality and efficiency for the prototyping part.展开更多
Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread popularity.However,most users cannot test the strength of printed parts,and little i...Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread popularity.However,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D printers.In this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were tested.The experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed HIPS.The prediction models of the process parameters were regressed to produce the optimal combination of process parameters.The experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile strength.With an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer thickness.In addition,they all increased with an increase of infill density.It was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were optimal.Our results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.展开更多
基金supported by Shandong Science Fund for Distinguished Young Scholars of China(JQ201715)National Natural Science Foundation of China(No.51575322)+1 种基金Major Program of Shandong Province Natural Science Foundation of China(ZR2018ZA0401 and ZR2018ZB0521)Key Research and Development Program of Shandong Province of China(2019GGX104049)。
文摘Fused deposition modeling(FDM)has unique advantages in the rapid prototyping of thermoplastics which have been developed in diverse fields.However,although great efforts have been made to optimize FDM process,the mechanical properties of printed parts are limited by the weak interlamination bonding as well as the poor performance of raw filaments used,such as acrylonitrile butadiene styrene(ABS),polylactic acid(PLA).Adding fibers into thermoplastic matrix and preparing high-performance filaments have been indicated to enhance the properties of fabricated parts.Recently,heat-resistant polyetheretherketone(PEEK)and its fiber reinforced composites were proposed for FDM process due to overcoming the limitation of equipment and process.However,few researches have been reported on the effects of FDM-3 D printing parameters on the mechanical properties of fiber reinforced PEEK composites.Therefore,5 wt%carbon fiber(CF)and glass fiber(GF)reinforced PEEK composite filaments were prepared respectively in this study.The effects of various printing parameters including nozzle temperature,platform temperature,printing speed and layer thickness on the mechanical properties(including tensile strength,flexural strength and impact strength)were surveyed.To analyze the microstructure and failure reasons of printed CF/PEEK and GF/PEEK samples,the tensile fractured surfaces were investigated via scanning electron microscope(SEM).
文摘Material extrusion additive manufacturing has rapidly grown in use for tissue engineering research since its adoption in the year 2000. It has enabled researchers to produce scaffolds with intricate porous geometries that were not feasible with traditional manufacturing processes. Researchers can control the structural geometry through a wide range of customisable printing parameters and design choices including material, print path, temperature, and many other process parameters. Currently, the impact of these choices is not fully understood. This review focuses on how the position and orientation of extruded filaments, which sometimes referred to as the print path, lay-down pattern, or simply'scaffold design', affect scaffold properties and biological performance. By analysing trends across multiple studies, new understanding was developed on how filament position affects mechanical properties. Biological performance was also found to be affected by filament position, but a lack of consensus between studies indicates a need for further research and understanding. In most research studies, scaffold design was dictated by capabilities of additive manufacturing software rather than free-form design of structural geometry optimised for biological requirements. There is scope for much greater application of engineering innovation to additive manufacture novel geometries. To achieve this, better understanding of biological requirements is needed to enable the effective specification of ideal scaffold geometries.
基金Supported by the Science and Technology Support Key Project of 12th Five-Year of China(2011BAD20B00-4)~~
文摘The influence of processing parameters on the precision of parts fabricated by fused deposition modeling （FDM） technology is studied based on a series of performed experiments. Processing parameters of FDM in terms of wire-width compensation, extrusion velocity, filing velocity, and layer thickness are chosen as the control fac- tors. Robust design analysis and multi-index fuzzy comprehensive assessment method are used to obtain the opti- mal parameters. Results show that the influencing degrees of these four factors on the precision of as-processed parts are different. The optimizations of individual parameters and their combined effects are of the same impor- tance for a high precision manufacturing.
基金supported by the National Natural Science Foundation of China(Grant No.51901082)the National Postdoctoral Program for Innovative Talents(BX20200137)the National Defense Basic Scientific Research Program of China(JCKY2018110C060)。
文摘Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requirements of high service temperature,high conductivity and high resolution remains a challenge.In this paper,a hybrid AM method combining the fused deposition modeling(FDM)and hydrophobic treatment assisted laser activation metallization(LAM)was proposed for manufacturing the polyetheretherketone(PEEK)-based 3D electronics,by which the conformal copper patterns were deposited on the 3D-printed PEEK parts,and the adhesion between them reached the 5B high level.Moreover,the 3D components could support the thermal cycling test from-55℃ to 125℃ for more than 100 cycles.Particularly,the application of a hydrophobic coating on the FDM-printed PEEK before LAM can promote an ideal catalytic selectivity on its surface,not affected by the inevitable printing borders and pores in the FDM-printed parts,then making the resolution of the electroless plated copper lines improved significantly.In consequence,Cu lines with width and spacing of only60μm and 100μm were obtained on both as-printed and after-polished PEEK substrates.Finally,the potential of this technique to fabricate 3D conformal electronics was demonstrated.
基金Supported by the Science and Technology Support Key Project of Jiangsu Province (DE2008365)~~
文摘Based on analyzing the influences of a slicing scheme on stair-stepping effect, supporting structure, efficiency and deformation, etc. , analytical hierarchical process （AHP） combining with fuzzy synthetic evaluation is introduced to make decision in slicing schemes for a processing part. The application in determining the slicing scheme for a computer mouse during prototyping shows that the method increases the rationality during decision- making and improves quality and efficiency for the prototyping part.
基金supported by the National Natural Science Foundation of China(Grant No.51975097)the National Key Research and Development Project(Grant No.2020YFA0713702).
文摘Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread popularity.However,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D printers.In this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were tested.The experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed HIPS.The prediction models of the process parameters were regressed to produce the optimal combination of process parameters.The experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile strength.With an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer thickness.In addition,they all increased with an increase of infill density.It was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were optimal.Our results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.
