scholarly journals PEEK filament characteristics before and after extrusion within fused filament fabrication process

2022 ◽  
Author(s):  
Cleiton André Comelli ◽  
Richard Davies ◽  
HenkJan van der Pol ◽  
Oana Ghita
Keyword(s):  
Mechanical Properties ◽  
Mechanical Performance ◽  
Extrusion Process ◽  
X Ray Diffraction ◽  
Fused Filament Fabrication ◽  
Scanning Calorimetry ◽  
Fast Scanning Calorimetry ◽  
Transmission Electron ◽  
Before And After ◽  
History Of

AbstractThe heating and extrusion process in fused filament fabrication (FFF) is significantly shorter than the conventional extrusion process where longer heating times and significant pressure are applied. For this reason, it is important to understand whether the crystal history of the feedstock is fully erased through the FFF process and whether the FFF process can be tailored further by engineering the crystallization of the feedstock filaments. In this context, a methodology for evaluating the influence of morphology and mechanical properties on different feedstock and extruded filaments is proposed. Filaments with three different PEEK 450G crystalline structures (standard crystallinity, drawn filament and amorphous filament) were selected and evaluated, before and after free extrusion. The resulting morphology, crystallinity and mechanical properties of the extruded filaments were compared against the feedstock properties. X-ray diffraction (XRD), transmission electron microscopy (TEM), differential and fast scanning calorimetry (DSC/FDSC) and tensile test were the techniques used to evaluate the materials. The results showed clear differences in the properties of the feedstock materials, while the analysis of the extruded filaments points to a homogenization of the resulting material producing mostly similar mechanical properties. However, the use of the drawn filament highlighted a statistically significant improvement in crystallinity and mechanical performance, especially in strain values. This conclusion suggests the innovative possibility of improving the quality of manufactured parts by tailoring the microstructure of the feedstock material used in the FFF process. Graphical abstract

scholarly journals Effects of Sintering Temperature on Densification, Microstructure and Mechanical Properties of Al-Based Alloy by High-Velocity Compaction

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Xianjie Yuan ◽  
Xuanhui Qu ◽  
Haiqing Yin ◽  
Zaiqiang Feng ◽  
Mingqi Tang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Velocity ◽  
Sintered Density ◽  
Sintering Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron ◽  
High Velocity Compaction ◽  
Sintered Temperature

This present work investigates the effects of sintering temperature on densification, mechanical properties and microstructure of Al-based alloy pressed by high-velocity compaction. The green samples were heated under the flow of high pure (99.99 wt%) N2. The heating rate was 4 °C/min before 315 °C. For reducing the residual stress, the samples were isothermally held for one h. Then, the specimens were respectively heated at the rate of 10 °C/min to the temperature between 540 °C and 700 °C, held for one h, and then furnace-cooled to the room temperature. Results indicate that when the sintered temperature was 640 °C, both the sintered density and mechanical properties was optimum. Differential Scanning Calorimetry, X-ray diffraction of sintered samples, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Transmission Electron Microscope were used to analyse the microstructure and phases.

Preparation of cross-linked PVC-g-(St-MA) copolymer/organoclay nanocomposites and investigation of chemical characteristics, morphology, thermal, and mechanical properties

2019 ◽  
pp. 089270571988601
Author(s):  
Reza Izadpanah ◽  
Mostafa Rezaei ◽  
Saeid Talebi
Keyword(s):  
Mechanical Properties ◽  
Clay Content ◽  
Thermomechanical Properties ◽  
Morphological Observation ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Bonding Interaction ◽  
Structure Morphology ◽  
Nanoclay Content

The goal of this work is to investigate the effect of incorporating organoclays on the cross-link structure, morphology, and thermomechanical properties of cross-linked organoclay/polyvinyl chloride grafted with styrene and maleic anhydride (PVC- g-(St-MA)) copolymer nanocomposites (CPN). Cloisite30B (C30B) and Cloisite15A (C15A) organoclays were used for the preparation of cross-linked PVC- g-(St-MA) nanocomposites by the solution mixing route. The nanoclay content in nanocomposites varied from 0.2 wt% to 1 wt%. The chemical structure and interaction between PVC- g-(St-MA) cross-linked segments and nanoclays were studied by Fourier transform infrared (FTIR) peaks deconvolution method. FTIR spectroscopy suggested the lowest extent of hydrogen bonding interaction for C30B containing sample, which decreased with clay content increment. The morphology of nanocomposites was studied by X-ray diffraction and transmission electron microscopy methods. Morphological observation revealed a near to the exfoliation state for organoclays in PVC- g-(St-MA) nanocomposite containing 1 wt% C30B. However, C15A/PVC- g-(St-MA) nanocomposite (C15A-CPN) exhibited partially intercalated and agglomerated morphology. Differential scanning calorimetry examination was conducted to measure the glass transition temperature ( T g) of the segments. At the same clay content, the T g of the C30B containing nanocomposites were higher than that of C15A samples. The mechanical properties of these nanocomposites were also investigated. As a consequence, C30B-CPN showed improved mechanical properties compared to C15A-CPN and cross-linked PVC- g-(St-MA) samples.

Effect of polyphosphate binding on the chain dynamic of caseins: investigation by differential scanning calorimetry and thermally stimulated currents

1988 ◽  
Vol 55 (3) ◽  
pp. 401-412 ◽  
Author(s):  
Alain Lamure ◽  
Jean-François Pommert ◽  
Alain Klaebe ◽  
Colette Lacabanne ◽  
Jean-Jacques Perie
Keyword(s):  
Differential Scanning Calorimetry ◽  
Structural Changes ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Thermally Stimulated Currents ◽  
Transmission Electron ◽  
Different Types ◽  
Before And After ◽  
Chain Dynamic

SummarySamples of caseins having different Ca contents as used in cheese processing were analysed by techniques using differential scanning calorimetry and thermally stimulated currents (TSC) before and after treatment with Na poly-phosphate, a food additive used in the manufacture of processed cheese. These techniques revealed structural changes induced by the salt, and the different types of water molecules associated with the protein are evident. This characterization is in agreement with results obtained by other techniques, particularly X-ray diffraction of proteins. Transmission electron microscopy of the same samples confirmed that the changes observed by TSC were associated with an unravelling of the protein.

Microstructure and Mechanical Properties of AISI 8620 Steel Processed by ECAP

2014 ◽  
Vol 1611 ◽  
pp. 89-94
Author(s):  
Diana M. Marulanda ◽  
Jair G. Cortés ◽  
Marco A. Pérez ◽  
Gabriel García
Keyword(s):  
Mechanical Properties ◽  
Mechanical Performance ◽  
Equivalent Strain ◽  
Sem Analysis ◽  
Structure Evolution ◽  
Low Carbon ◽  
X Ray Diffraction ◽  
X Ray ◽  
Angular Pressing ◽  
Before And After

ABSTRACTThe aim of this work is to process by equal channel angular pressing (ECAP) a low carbon – triple-alloyed steel containing 0.2% C, 0.5% Cr, 0.6% Ni, 0.2% Mo and 0.8 Mo. The process is performed at room temperature for up to four passes using route Bc with an equivalent strain of ∼0.6 after a single pass. Structure evolution before and after deformation is studied using scanning electron microscopy (SEM) and x-ray diffraction (XRD) and mechanical properties are assessed by microhardness and tensile testing. A significant improvement of the mechanical properties is found with increasing number of ECAP passes. Micro-hardness increases from 216 HV for the initial sample to 302 HV after four passes and tensile strength increases to 1200 MPa compared with 430 MPa prior to ECAP. X-ray diffraction and SEM analysis show changes in the original ferritic-perlitic structure through ferrite grain refinement and the deformation of perlite. This nickel-chromium-molybdenum alloy is used in manufacturing as gear material, and when it is hardened and formed through carburizing or boronizing it can be used to make hard-wearing machine parts. However, the ECAP process has not been used to harden this steel and to change its structure to obtain better mechanical performance.

scholarly journals Structure and Mechanical Properties of High-Density Polyethylene Composites Reinforced with Glassy Carbon

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4024
Author(s):  
Piotr Olesik ◽  
Marcin Godzierz ◽  
Mateusz Kozioł ◽  
Jakub Jała ◽  
Urszula Szeluga ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Glassy Carbon ◽  
High Density Polyethylene ◽  
Mechanical Performance ◽  
High Density ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Carbon Fillers ◽  
Composite Samples

In this paper, we investigated theimpact of glassy carbon (GC) reinforcement oncrystal structure and the mechanical performance of high-density polyethylene (HDPE). We made composite samples by mixing HDPE granules with powder in ethanol followed bymelt mixing in a laboratory extruder. Along with the investigated composite, we also prepared samples with carbon nanotubes (CNT), graphene (GNP) and graphite (Gr) to compare GC impact with already used carbon fillers. To evaluate crystal structure and crystallinity, we used X-ray diffraction (XRD) and differential scanning calorimetry (DSC). We supported the XRD results with a residual stress analysis (RSA) according to the EN15305 standard. Analysis showed that reinforcing with GC leads to significant crystallite size reduction and low residual stress values. We evaluated the mechanical properties of composites with hardness and tensile testing. The addition of glassy carbon results inincreased mechanical strength incomposites with CNT and GNP.

Silica/GO hybrids reinforced NR: Better interface interaction and dynamic behavior

2019 ◽  
Vol 52 (7) ◽  
pp. 575-592
Author(s):  
Kaikai Liu ◽  
Yuanyuan Shang ◽  
Liu Yang ◽  
Aihua Du
Keyword(s):  
Mechanical Performance ◽  
Volume Fraction ◽  
High Volume ◽  
Interfacial Interaction ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Interface Interaction ◽  
Transmission Electron ◽  
Strong Interfacial Interaction ◽  
Filler Dispersion

With silica firstly modified by 3-aminopropyl-triethoxysilane (APES), graphene oxide (GO) was prepared by modified Hummer’s method. APES-silica/GO (AsGO) hybrids were fabricated through hydrogen bond to reduce the polarity of silica and GO and increase the compatibility between natural rubber (NR) and AsGO. Subsequently, AsGO was incorporated into NR latex. The interaction between GO and silica in AsGO was characterized by X-ray diffraction, Raman, and Zeta potential. It was confirmed by transmission electron microscopy that the silica was uniformly dispersed on the surface of the GO. The filler–rubber interfacial interaction was thoroughly investigated. The amount of constrained region was quantified through differential scanning calorimetry results, and it showed that the high volume fraction of constrained region is responsible for the strong interfacial interaction. Besides, the mechanical performance, dynamic property, and electrical and thermal conductivity of NR-AsG x were studied. The results showed that the overall performance of NR-AsG x has an optimum value when the GO loading is 1.5 phr, which is due to the good filler dispersion and strong interface interaction.

scholarly journals Generation of Wholly Thermoplastic Composites and Their Processing in Additive Manufacturing

2021 ◽  
Author(s):  
Tianran Chen
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
High Performance ◽  
Liquid Crystalline ◽  
Mechanical Performance ◽  
Crystalline Polymer ◽  
Extrusion Process ◽  
Thermoplastic Composites ◽  
Fiber Reinforced ◽  
Fused Filament Fabrication

3D printing has attracted great interest over the past three decades due to its high precision, less waste generation and design freedom [1-3]. One of the major challenges 3D printing is the poor mechanical performance of pure polymer parts. Researchers used traditional carbon and glass fiber reinforced composites to overcome this issue [4-7]. The traditional fibers can improve the mechanical properties of printed parts. However, the manufacturing techniques and printing process restrict the overall performance of the printed parts. Thermotropic liquid crystalline polymer (TLCP) is another reinforcement which offers lighter weight, lower viscosity, excellent mechanical performance and great recyclability [8-15]. TLCPs are capable of forming extended conformations when subjected to extensional or shear deformation.[16, 17] The formation of highly orientated molecular structure enables the generation of high mechanical properties. In this study, polyamide was reinforced with TLCP by the dual-extrusion technique to generate high performance composite filaments [18]. Rheological tests were used to optimize the processing conditions of the dual-extrusion process, which could minimize the degradation of matrix polymer. High performance and lightweight fiber-reinforced composite parts were fabricated by utilizing the fused filament fabrication (FFF) technique. The composite filaments were printed at the temperature below the melting point of TLCP to avoid the relaxation of TLCP. The mechanical performances of printed parts are greater than 3D printed parts which are reinforced by conventional fibers.

scholarly journals Generation of Wholly Thermoplastic Composites and Their Processing in Additive Manufacturing

2021 ◽  
Author(s):  
Tianran Chen ◽  
Donald Baid
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
High Performance ◽  
Liquid Crystalline ◽  
Mechanical Performance ◽  
Crystalline Polymer ◽  
Extrusion Process ◽  
Thermoplastic Composites ◽  
Fiber Reinforced ◽  
Fused Filament Fabrication

3D printing has attracted great interest over the past three decades due to its high precision, less waste generation and design freedom[1-3]. One of the major challenges 3D printing is the poor mechanical performance of pure polymer parts. Researchers used traditional carbon and glass fiber reinforced composites to overcome this issue [4-7]. The traditional fibers can improve the mechanical properties of printed parts. However, the manufacturing techniques and printing process restrict the overall performance of the printed parts. Thermotropic liquid crystalline polymer (TLCP) is another reinforcement which offers lighter weight, lower viscosity, excellent mechanical performance and great recyclability [8-15]. TLCPs are capable of forming extended conformations when subjected to extensional or shear deformation.[16, 17] The formation of highly orientated molecular structure enables the generation of high mechanical properties . In this study, polyamide was reinforced with TLCP by the dual-extrusion technique to generate high performance composite filaments [18]. Rheological tests were used to optimize the processing conditions of the dual-extrusion process, which could minimize the degradation of matrix polymer. High performance and lightweight fiber-reinforced composite parts were fabricated by utilizing the fused filament fabrication (FFF) technique. The composite filaments were printed at the temperature below the melting point of TLCP to avoid the relaxation of TLCP. The mechanical performances of printed parts are greater than 3D printed parts which are reinforced by conventional fibers.

scholarly journals Effect of Organoclay on the Morphology, and Thermal Properties of Polystyrene/Poly (vinyl chloride) Nanocomposites

2015 ◽  
Vol 1 (2) ◽  
Author(s):  
Jumaa Aseeri - Waffa Mekhamer -  Naser Alandis
Keyword(s):  
Vinyl Chloride ◽  
Cetylpyridinium Chloride ◽  
Clay Sample ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Dsc Studies ◽  
Poly Vinyl Chloride ◽  
Transmission Electron ◽  
Before And After ◽  
Na Ions

Polystyrene and poly (vinyl chloride) (PS/PVC) were prepared via solvent casting method with different weight ratios of PS/PVC:  (100/0, 90/10, 80/20, 10/90 and 0/100) to investigate their miscibility. We have studied the morphology of blend PS90/PVC10 (Pd1) with different content (1, 3, 10 %) of organoclay (MM). Cetylpyridinium chloride (CPC) is used to modify the clay sample after saturating its surface with Na+ ions. Fourier transform infrared (FTIR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize the clay sample before and after modification by CPC. The blend miscibility has been confirmed by FTIR, XRD, differential scanning calorimetry (DSC) studies.  The prepared nanocomposites were characterized using FTIR, DSC, TEM and scanning electron microscope (SEM). We observed that MM have a significant effect on improvement the miscibility of PS/PVC blends. The thermal stability of the nanocomposites was measured using thermogravimetric analysis (TGA).

scholarly journals Thermal treatment of magnetite nanoparticles

2015 ◽  
Vol 6 ◽  
pp. 1385-1396 ◽  
Author(s):  
Beata Kalska-Szostko ◽  
Urszula Wykowska ◽  
Dariusz Satula ◽  
Per Nordblad
Keyword(s):  
Thermal Stability ◽  
Thermal Treatment ◽  
Magnetite Nanoparticles ◽  
Surface Characteristics ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron ◽  
Before And After ◽  
Thermal Stability Of

This paper presents the results of a thermal treatment process for magnetite nanoparticles in the temperature range of 50–500 °C. The tested magnetite nanoparticles were synthesized using three different methods that resulted in nanoparticles with different surface characteristics and crystallinity, which in turn, was reflected in their thermal durability. The particles were obtained by coprecipitation from Fe chlorides and decomposition of an Fe(acac)3 complex with and without a core–shell structure. Three types of ferrite nanoparticles were produced and their thermal stability properties were compared. In this study, two sets of unmodified magnetite nanoparticles were used where crystallinity was as determinant of the series. For the third type of particles, a Ag shell was added. By comparing the coated and uncoated particles, the influence of the metallic layer on the thermal stability of the nanoparticles was tested. Before and after heat treatment, the nanoparticles were examined using transmission electron microscopy, IR spectroscopy, differential scanning calorimetry, X-ray diffraction and Mössbauer spectroscopy. Based on the obtained results, it was observed that the fabrication methods determine, to some extent, the sensitivity of the nanoparticles to external factors.

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