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Article ; Online: Dynamic Composite Materials Characterisation with Hopkinson Bars

Mostapha Tarfaoui

Journal of Composites Science, Vol 7, Iss 33, p

Design and Development of New Dynamic Compression Systems

2023 Volume 33

Abstract: The split Hopkinson pressure bars (SHPB) system is the most commonly employed machine to study the dynamic characteristics of different materials under high strain rates. In this research, a numerical investigation is carried out to study different bar ... ...

Abstract	The split Hopkinson pressure bars (SHPB) system is the most commonly employed machine to study the dynamic characteristics of different materials under high strain rates. In this research, a numerical investigation is carried out to study different bar shapes such as square, hexagonal, and triangular cross-sections and to compare them with the standard cylindrical bars. The 3D finite element model developed for circular cross-sectional shapes was first validated with the experimental results and then compared with the other proposed shapes. In most scientific research, cylindrical cross-section bars with a square cross-section specimen are traditionally used as they have several advantages, such as in situ imaging of the side surfaces of the specimen during stress wave propagation. Moreover, the flat surfaces of the proposed shapes counter the problem of debonding strain gauges, especially at high impact pressures. Comparison of the results showed an excellent confirmation of the sample dynamic behaviour and different geometric shapes of the bar geometries, which validates the choice of the appropriate system.
Keywords	composite materials ; split Hopkinson pressure bar ; high strain rate ; bar shape ; material characterisation ; dynamic behaviour ; Technology ; T ; Science ; Q
Subject code	670
Language	English
Publishing date	2023-01-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: FDM technology and the effect of printing parameters on the tensile strength of ABS parts.

Daly, Mohamed / Tarfaoui, Mostapha / Chihi, Manel / Bouraoui, Chokri

The International journal, advanced manufacturing technology

2023 Volume 126, Issue 11-12, Page(s) 5307–5323

Abstract: The effect of printing speed on the tensile strength of acrylonitrile butadiene styrene (ABS) samples fabricated using the fused deposition modelling (FDM) process is addressed in this research. The mechanical performance of FDM-ABS products was ... ...

Abstract	The effect of printing speed on the tensile strength of acrylonitrile butadiene styrene (ABS) samples fabricated using the fused deposition modelling (FDM) process is addressed in this research. The mechanical performance of FDM-ABS products was evaluated using four different printing speeds (10, 30, 50, and 70 mm/s). A numerical model was developed to simulate the experimental campaign by coupling two computational codes, Abaqus and Digimat. In addition, this article attempts to investigate the impacts of printing parameters on ASTM D638 ABS specimens. A 3D thermomechanical model was implemented to simulate the printing process and evaluate the printed part quality by analysing residual stress, temperature gradient and warpage. Several parts printed in Digimat were analysed and compared numerically. The parametric study allowed us to quantify the effect of 3D printing parameters such as printing speed, printing direction, and the chosen discretisation (layer by layer or filament) on residual stresses, deflection, warpage, and resulting mechanical behaviour.
Language	English
Publishing date	2023-05-01
Publishing country	England
Document type	Journal Article
ZDB-ID	1476510-X
ISSN	1433-3015 ; 0268-3768
ISSN (online)	1433-3015
ISSN	0268-3768
DOI	10.1007/s00170-023-11486-y
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Additive Manufacturing and Composite Materials for Marine Energy: Case of Tidal Turbine.

Rouway, Marwane / Tarfaoui, Mostapha / Chakhchaoui, Nabil / Omari, Lhaj El Hachemi / Fraija, Fouzia / Cherkaoui, Omar

3D printing and additive manufacturing

2023 Volume 10, Issue 6, Page(s) 1309–1319

Abstract: The global trend in additive manufacturing is the technology of three-dimensional (3D) printing with a high potential to avoid some of the weaknesses of conventional fabrication techniques. This new technology has been used to manufacture small tidal and ...

Abstract	The global trend in additive manufacturing is the technology of three-dimensional (3D) printing with a high potential to avoid some of the weaknesses of conventional fabrication techniques. This new technology has been used to manufacture small tidal and wind turbines. In isolated areas, small turbines can be manufactured and assembled on-site for green energy production. The purpose of this document is to evaluate the thermomechanical behavior of a printed tidal turbine using Digimat-AM (Additive Manufacturing) with fused filament fabrication method. The finite element computes the mechanical deflection, temperature, residual stresses, and warpage fields of the printed part. The composites used during printing are thermoplastic polymers (acrylonitrile butadiene styrene, polyamide 6 [PA6], polyamide 12 [PA12], and polyetherimide [PEI]) reinforced with carbon and glass fillers in the form of fibers and beads (CF/GF and CB/GB). Through the simulation, one could show that the blade printed with PEI-CB/CF has excellent mechanical performance of low mechanical deflection and warpage, compared to PA6-CB/CF. In addition, the fiber-shaped fillers are better than the bead-shaped ones for the 3D printing process. In general, this study has shown the potential and feasibility of 3D printing as an excellent opportunity in the fabrication of small blades in the future, but more studies are required to understand this potential.
Language	English
Publishing date	2023-12-11
Publishing country	United States
Document type	Journal Article
ISSN	2329-7670
ISSN (online)	2329-7670
DOI	10.1089/3dp.2021.0194
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Article ; Online: COVID-19: Current challenges regarding medical healthcare supplies and their implications on the global additive manufacturing industry.

Goda, Ibrahim / Nachtane, Mourad / Qureshi, Yumna / Benyahia, Hamza / Tarfaoui, Mostapha

Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine

2022 Volume 236, Issue 5, Page(s) 613–627

Abstract: The covid-19 outbreak has caused a shortage of masks and other healthcare products for the general public around the globe. In addition, it has also affected the supply of personal protective equipment (PPE) used by healthcare services because of a ... ...

Abstract	The covid-19 outbreak has caused a shortage of masks and other healthcare products for the general public around the globe. In addition, it has also affected the supply of personal protective equipment (PPE) used by healthcare services because of a sudden increase in their demand. This significant disruption in the global supply chain of these products resulted in, leaving many staff and patients without protection. The additive manufacturing (AM) industry is going through extraordinary times and can provide emergency responses to help deal with the global crisis caused by the COVID-19 pandemic. The objective of the present work is therefore to perform an up-to-date review to determine the capacity of AM to provide exclusive benefits for the medical healthcare supplies sector to fight this current situation. In this review, it is found that AM technology has proved that it can be used as a volume manufacturing technology for the ongoing crisis. However, the standardization and certification are appeared to represent the main challenges for adopting the AM in healthcare against COVID-19. Furthermore, additively manufactured materials for medical applications must be developed for medical environments. Most printed medical products for COVID-19 require biocompatibility evaluation and shall prove their ability to sterilize. Finally, this review concluded that AM technology can fulfill the requirements of face masks and ventilator parts for healthcare systems for proper controlling and treating of COVID-19 patients when the safety and efficacy of these devices are ensured.
MeSH term(s)	COVID-19/epidemiology ; Delivery of Health Care ; Humans ; Manufacturing Industry ; Pandemics/prevention & control ; SARS-CoV-2
Language	English
Publishing date	2022-01-22
Publishing country	England
Document type	Journal Article ; Review
ZDB-ID	1065942-0
ISSN	2041-3033 ; 0046-2039 ; 0954-4119
ISSN (online)	2041-3033
ISSN	0046-2039 ; 0954-4119
DOI	10.1177/09544119211070373
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Article ; Online: The Effect of Agglomeration on the Electrical and Mechanical Properties of Polymer Matrix Nanocomposites Reinforced with Carbon Nanotubes.

Tamayo-Vegas, Sebastian / Muhsan, Ali / Liu, Chang / Tarfaoui, Mostapha / Lafdi, Khalid

Polymers

2022 Volume 14, Issue 9

Abstract: In this work, we investigated the effect of carbon nanotubes addition and agglomeration formation on the mechanical and electrical properties of CNT-polymer-based nanocomposites. Six specimens with carbon nanotubes (CNTs) fractions of 0%, 0.5%, 1%, 2%, 4% ...

Abstract	In this work, we investigated the effect of carbon nanotubes addition and agglomeration formation on the mechanical and electrical properties of CNT-polymer-based nanocomposites. Six specimens with carbon nanotubes (CNTs) fractions of 0%, 0.5%, 1%, 2%, 4% and 5% were manufactured and characterized by dynamic mechanical analysis (DMA) and four-probe method. The stress-strain curves and electrical conductivity properties were obtained. Scanning electron microscopy (SEM) was used to characterize both agglomeration and porosity formation. By employing micromechanics, through representative volume element (RVE), finite element analysis (FEA) and resistor network model (RNM), the Young's modulus and electrical conductivity values were calculated. The samples' elastic moduli showed an increment, reaching the maximum value at a CNTs fraction of 2%, thereafter an adverse effect was caused in the high CNT percentage samples. The final electrical conductivity seemed greatly altered with the addition of CNTs, reaching the percolation threshold at 2%. The unavoidable formation of CNT agglomerates appeared to influence the final physical properties. The CNT agglomerates adversely affect the mechanical performance of high-CNT-percentage samples. Conversely, an exponential increment in the electrical conductivity was presented as the agglomerates formed networks allowing the transport of electrons through the tunnelling effect. These phenomena were experimentally and numerically confirmed, showing a good correlation.
Language	English
Publishing date	2022-04-29
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2527146-5
ISSN	2073-4360 ; 2073-4360
ISSN (online)	2073-4360
ISSN	2073-4360
DOI	10.3390/polym14091842
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Article ; Online: Poly(Lactic Acid) (PLA)-Based Nanocomposites

Sabrine Khammassi / Mostapha Tarfaoui / Kateřina Škrlová / Dagmar Měřínská / Daniela Plachá / Fouad Erchiqui

Journal of Composites Science, Vol 6, Iss 112, p

Impact of Vermiculite, Silver, and Graphene Oxide on Thermal Stability, Isothermal Crystallization, and Local Mechanical Behavior

2022 Volume 112

Abstract: The structural, thermal, and mechanical properties of unreinforced and reinforced polylactic acid (PLA) were investigated. The PLA was a biopolymer that was reinforced with four fillers (i.e., graphene oxide (GO) and silver (Ag); vermiculite (VMT) and ... ...

Abstract	The structural, thermal, and mechanical properties of unreinforced and reinforced polylactic acid (PLA) were investigated. The PLA was a biopolymer that was reinforced with four fillers (i.e., graphene oxide (GO) and silver (Ag); vermiculite (VMT) and silver (Ag); and two organically modified vermiculites). The processing technique for the production of the composite materials were carefully planned. The PLA nanocomposites were investigated by examining their morphological aspects, changes in PLA phases and transitions and, most importantly, the effect on certain final properties. X-ray diffraction and differential scanning calorimetry (DSC) analysis indicated that the sample was completely amorphous. Thermogravimetric analysis (TGA) results indicated that the presence of reinforcing particles in the PLA matrix did not affect the thermal degradation of these composites. Furthermore, the local mechanical properties were investigated using the microindentation method to evaluate the effect of different nanofillers. Scanning electron microscopy (SEM) and a VHX-500 optical digital microscope (Keyence International, Mechelen, Belgium) were also used to examine the surface morphology of the PLA polymer composites. These results can help to select suitable fillers to enhance the PLA performance of biopolymers.
Keywords	polylactide ; composites ; thermal stability ; isothermal crystallization ; microindentation ; Technology ; T ; Science ; Q
Language	English
Publishing date	2022-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The Effect of Agglomeration on the Electrical and Mechanical Properties of Polymer Matrix Nanocomposites Reinforced with Carbon Nanotubes

Sebastian Tamayo-Vegas / Ali Muhsan / Chang Liu / Mostapha Tarfaoui / Khalid Lafdi

Polymers, Vol 14, Iss 1842, p

2022 Volume 1842

Abstract: In this work, we investigated the effect of carbon nanotubes addition and agglomeration formation on the mechanical and electrical properties of CNT–polymer-based nanocomposites. Six specimens with carbon nanotubes (CNTs) fractions of 0%, 0.5%, 1%, 2%, 4% ...

Abstract	In this work, we investigated the effect of carbon nanotubes addition and agglomeration formation on the mechanical and electrical properties of CNT–polymer-based nanocomposites. Six specimens with carbon nanotubes (CNTs) fractions of 0%, 0.5%, 1%, 2%, 4% and 5% were manufactured and characterized by dynamic mechanical analysis (DMA) and four-probe method. The stress–strain curves and electrical conductivity properties were obtained. Scanning electron microscopy (SEM) was used to characterize both agglomeration and porosity formation. By employing micromechanics, through representative volume element (RVE), finite element analysis (FEA) and resistor network model (RNM), the Young’s modulus and electrical conductivity values were calculated. The samples’ elastic moduli showed an increment, reaching the maximum value at a CNTs fraction of 2%, thereafter an adverse effect was caused in the high CNT percentage samples. The final electrical conductivity seemed greatly altered with the addition of CNTs, reaching the percolation threshold at 2%. The unavoidable formation of CNT agglomerates appeared to influence the final physical properties. The CNT agglomerates adversely affect the mechanical performance of high-CNT-percentage samples. Conversely, an exponential increment in the electrical conductivity was presented as the agglomerates formed networks allowing the transport of electrons through the tunnelling effect. These phenomena were experimentally and numerically confirmed, showing a good correlation.
Keywords	nanocomposites ; agglomeration ; electrical properties ; mechanical properties ; computational modelling ; multi-scale modelling ; Organic chemistry ; QD241-441
Language	English
Publishing date	2022-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: An Overview of the Recent Advances in Composite Materials and Artificial Intelligence for Hydrogen Storage Vessels Design

Mourad Nachtane / Mostapha Tarfaoui / Mohamed amine Abichou / Alexandre Vetcher / Marwane Rouway / Abdeouhaed Aâmir / Habib Mouadili / Houda Laaouidi / Hassan Naanani

Journal of Composites Science, Vol 7, Iss 119, p

2023 Volume 119

Abstract: The environmental impact of CO 2 emissions is widely acknowledged, making the development of alternative propulsion systems a priority. Hydrogen is a potential candidate to replace fossil fuels for transport applications, with three technologies ... ...

Abstract	The environmental impact of CO 2 emissions is widely acknowledged, making the development of alternative propulsion systems a priority. Hydrogen is a potential candidate to replace fossil fuels for transport applications, with three technologies considered for the onboard storage of hydrogen: storage in the form of a compressed gas, storage as a cryogenic liquid, and storage as a solid. These technologies are now competing to meet the requirements of vehicle manufacturers; each has its own unique challenges that must be understood to direct future research and development efforts. This paper reviews technological developments for Hydrogen Storage Vessel (HSV) designs, including their technical performance, manufacturing costs, safety, and environmental impact. More specifically, an up-to-date review of fiber-reinforced polymer composite HSVs was explored, including the end-of-life recycling options. A review of current numerical models for HSVs was conducted, including the use of artificial intelligence techniques to assess the performance of composite HSVs, leading to more sophisticated designs for achieving a more sustainable future.
Keywords	hydrogen storage ; composite materials ; transport applications ; circular economy ; recycling ; artificial intelligence ; Technology ; T ; Science ; Q
Subject code	621
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Effect of CNTs Additives on the Energy Balance of Carbon/Epoxy Nanocomposites during Dynamic Compression Test.

Chihi, Manel / Tarfaoui, Mostapha / Bouraoui, Chokri / El Moumen, Ahmed

Polymers

2020 Volume 12, Issue 1

Abstract: Previous research has shown that nanocomposites show not only enhancements in mechanical properties (stiffness, fracture toughness) but also possess remarkable energy absorption characteristics. However, the potential of carbon nanotubes (CNTs) as ... ...

Abstract	Previous research has shown that nanocomposites show not only enhancements in mechanical properties (stiffness, fracture toughness) but also possess remarkable energy absorption characteristics. However, the potential of carbon nanotubes (CNTs) as nanofiller in reinforced epoxy composites like glass fiber-reinforced polymers (GFRP) or carbon fiber-reinforced polymers (CFRP) under dynamic testing is still underdeveloped. The goal of this study is to investigate the effect of integrating nanofillers such as CNTs into the epoxy matrix of carbon fiber reinforced polymer composites (CFRP) on their dynamic energy absorption potential under impact. An out-of-plane compressive test at high strain rates was performed using a Split Hopkinson Pressure Bar (SHPB), and the results were analyzed to study the effect of changing the concentration of CNTs on the energy absorption properties of the nanocomposites. A strong correlation between strain rates and CNT mass fractions was found out, showing that an increase in percentage of CNTs could enhance the dynamic properties and energy absorption capabilities of fiber-reinforced composites.
Language	English
Publishing date	2020-01-11
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2527146-5
ISSN	2073-4360 ; 2073-4360
ISSN (online)	2073-4360
ISSN	2073-4360
DOI	10.3390/polym12010194
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: 3D Printing to Support the Shortage in Personal Protective Equipment Caused by COVID-19 Pandemic.

Tarfaoui, Mostapha / Nachtane, Mourad / Goda, Ibrahim / Qureshi, Yumna / Benyahia, Hamza

Materials (Basel, Switzerland)

2020 Volume 13, Issue 15

Abstract: Currently, the emergence of a novel human coronavirus disease, named COVID-19, has become a great global public health concern causing severe respiratory tract infections in humans. Yet, there is no specific vaccine or treatment for this COVID-19 where ... ...

Abstract	Currently, the emergence of a novel human coronavirus disease, named COVID-19, has become a great global public health concern causing severe respiratory tract infections in humans. Yet, there is no specific vaccine or treatment for this COVID-19 where anti-disease measures rely on preventing or slowing the transmission of infection from one person to another. In particularly, there is a growing effort to prevent or reduce transmission to frontline healthcare professionals. However, it is becoming an increasingly international concern respecting the shortage in the supply chain of critical single-use personal protective equipment (PPE). To that scope, we aim in the present work to provide a comprehensive overview of the latest 3D printing efforts against COVID-19, including professional additive manufacturing (AM) providers, makers and designers in the 3D printing community. Through this review paper, the response to several questions and inquiries regarding the following issues are addressed: technical factors connected with AM processes; recommendations for testing and characterizing medical devices that additively manufactured; AM materials that can be used for medical devices; biological concerns of final 3D printed medical parts, comprising biocompatibility, cleaning and sterility; and limitations of AM technology.
Keywords	covid19
Language	English
Publishing date	2020-07-27
Publishing country	Switzerland
Document type	Journal Article ; Review
ZDB-ID	2487261-1
ISSN	1996-1944
ISSN	1996-1944
DOI	10.3390/ma13153339
Database	MEDical Literature Analysis and Retrieval System OnLINE

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