Processing and characterization of the thermoplastic composites manufactured by ultrasonic vibration–assisted automated fiber placement

To obtain the autoclave-level mechanical properties using in situ consolidation of thermoplastic composites by automated fiber placement (AFP) with high efficiency is the focus of recent research. Different heat resources were utilized to pursue improved mechanical properties and deposition rates but yet not very satisfactory. In this article, E-glass fiber/polypropylene laminates, manufactured by ultrasonic vibration–assisted AFP (UAFP) and autoclave, were compared by means of mechanical properties and crystallization. The interfacial bonding mechanism was analyzed theoretically based on the principle of ultrasonic heating and the autohesion. The orthogonal tests were designed to study the effect of the process parameters on the interlaminar shear strength (ILSS), including the ultrasonic amplitude, layup speed, and pressure, to optimize the manufacturing process of specimens. The mechanical tests and differential scanning calorimetry (DSC) were utilized to evaluate the ILSS, mode I interlaminar fracture toughness GIC, impact toughness, and degree of crystalline of laminates from hot-press and UAFP. The experimental results indicate that the ILSS of the specimens from UAFP can match with the hot-press specimens. The GIC and the impact toughness of the UAFP specimens are 59.9% and 20.1% lower than the hot-press ones, respectively, which are due to the lower degree of crystalline caused by the higher cooling rate during the UAFP process. The results of DSC show that the crystallinity of specimens made from UAFP is only 38.5%, whereas the 49.2% crystallinity is tested for the hot-press.

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Processing of thermoplastic matrix composites through automated fiber placement and tape laying methods

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717738305 ◽

2017 ◽

Vol 31 (12) ◽

pp. 1676-1725 ◽

Cited By ~ 15

Author(s):

Khaled Yassin ◽

Mehdi Hojjati

Keyword(s):

Heat Transfer ◽

Quality Parameters ◽

Thermoplastic Composites ◽

Transfer Model ◽

Scanning Calorimetry ◽

Intimate Contact ◽

Fiber Placement ◽

Hot Gas ◽

Lap Shear ◽

Automated Fiber Placement

Fiber-reinforced composite materials are replacing metallic components due to their higher specific strength and stiffness. Automation and thermoplastics emerged to overcome the time and labor intensive manual techniques and the long curing cycles associated with processing thermoset-based composites. Thermoplastics are processed through fusion bonding which involves applying heat and pressure at the interface. Together with automated techniques (such as automated fiber placement, and automated tape laying), a fast, clean, out-of-autoclave, and automated process can be obtained. A detailed review of thermoplastic composites processing through automated methods is presented. It sheds the light on the materials used and the different heat sources incorporated with the pros and cons of each, with concentration mainly on hot gas torch, laser, and ultrasonic heating. A thorough illustration of the several mechanisms involved in a tow/tape placement process is tackled such as heat transfer, intimate contact development, molecular interdiffusion, void consolidation and growth, thermal degradation, crystallization, and so on. Few gaps and recommendations are included related to materials, laser heat source, heat transfer model, and the use of silicone rubber rollers. A review of optimization studies for tape placement processes is summarized including the main controllable variables and product quality parameters (or responses), with some of the major findings for laser and hot gas torch systems being presented. Both mechanical and physical characterizations are also reviewed including several testing techniques such as short beam shear, double cantilever beam, lap shear, wedge peel, differential scanning calorimetry, and so on. Challenges, however, still exist, such as achieving the autoclave-level mechanical properties and complying with the porosity levels required by the aerospace industry. More work is still necessary to overcome these challenges as well as increase the throughput of the process before it can be totally commercialized.

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Review: Filament Winding and Automated Fiber Placement with In Situ Consolidation for Fiber Reinforced Thermoplastic Polymer Composites

Polymers ◽

10.3390/polym13121951 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1951

Author(s):

Yi Di Boon ◽

Sunil Chandrakant Joshi ◽

Somen Kumar Bhudolia

Keyword(s):

Processing Parameters ◽

Filament Winding ◽

Reference Points ◽

Thermoplastic Composites ◽

Manufacturing Processes ◽

Fiber Reinforced ◽

Consolidation Process ◽

Fiber Placement ◽

Automated Fiber Placement

Fiber reinforced thermoplastic composites are gaining popularity in many industries due to their short consolidation cycles, among other advantages over thermoset-based composites. Computer aided manufacturing processes, such as filament winding and automated fiber placement, have been used conventionally for thermoset-based composites. The automated processes can be adapted to include in situ consolidation for the fabrication of thermoplastic-based composites. In this paper, a detailed literature review on the factors affecting the in situ consolidation process is presented. The models used to study the various aspects of the in situ consolidation process are discussed. The processing parameters that gave good consolidation results in past studies are compiled and highlighted. The parameters can be used as reference points for future studies to further improve the automated manufacturing processes.

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Effect of toughened polyamide-coated carbon fiber fabric on the mechanical performance and fracture toughness of CFRP

Journal of Composite Materials ◽

10.1177/0021998321999458 ◽

2021 ◽

pp. 002199832199945

Author(s):

Jong H Eun ◽

Bo K Choi ◽

Sun M Sung ◽

Min S Kim ◽

Joon S Lee

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Photoelectron Spectroscopy ◽

Mechanical Performance ◽

Epoxy Composites ◽

Scanning Calorimetry ◽

Internal Damage ◽

Impact Tests ◽

Flexural Tests ◽

The Impact

In this study, carbon/epoxy composites were manufactured by coating with a polyamide at different weight percentages (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve their impact resistance and fracture toughness. The chemical reaction between the polyamide and epoxy resin were examined by fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray photoelectron spectroscopy. The mechanical properties and fracture toughness of the carbon/epoxy composites were analyzed. The mechanical properties of the carbon/epoxy composites, such as transverse flexural tests, longitudinal flexural tests, and impact tests, were investigated. After the impact tests, an ultrasonic C-scan was performed to reveal the internal damage area. The interlaminar fracture toughness of the carbon/epoxy composites was measured using a mode I test. The critical energy release rates were increased by 77% compared to the virgin carbon/epoxy composites. The surface morphology of the fractured surface was observed. The toughening mechanism of the carbon/epoxy composites was suggested based on the confirmed experimental data.

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Mechanical, Thermal and Rheological Properties of Polyethylene-Based Composites Filled with Micrometric Aluminum Powder

Materials ◽

10.3390/ma13051242 ◽

2020 ◽

Vol 13 (5) ◽

pp. 1242

Author(s):

Olga Mysiukiewicz ◽

Paulina Kosmela ◽

Mateusz Barczewski ◽

Aleksander Hejna

Keyword(s):

Mechanical Properties ◽

Melt Flow Index ◽

Tensile Tests ◽

Mechanical Analysis ◽

Flow Index ◽

Scanning Calorimetry ◽

Metal Composites ◽

Pre Treatment ◽

The Impact ◽

Properties Of Composites

Investigations related to polymer/metal composites are often limited to the analysis of the electrical and thermal conductivity of the materials. The presented study aims to analyze the impact of aluminum (Al) filler content (from 1 to 20 wt%) on the rarely investigated properties of composites based on the high-density polyethylene (HDPE) matrix. The crystalline structure, rheological (melt flow index and oscillatory rheometry), thermal (differential scanning calorimetry), as well as static (tensile tests, hardness, rebound resilience) and dynamic (dynamical mechanical analysis) mechanical properties of composites were investigated. The incorporation of 1 and 2 wt% of aluminum filler resulted in small enhancements of mechanical properties, while loadings of 5 and 10 wt% provided materials with a similar performance to neat HDPE. Such results were supported by the lack of disturbances in the rheological behavior of composites. The presented results indicate that a significant content of aluminum filler may be introduced into the HDPE matrix without additional pre-treatment and does not cause the deterioration of composites’ performance, which should be considered beneficial when engineering PE/metal composites.

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Mechanical Properties of Equal-Channel Angular Extrusion-Processed Al-20Zn Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.445.195 ◽

2012 ◽

Vol 445 ◽

pp. 195-200

Author(s):

Murat Aydin ◽

Yakup Heyal

Keyword(s):

Mechanical Properties ◽

Impact Toughness ◽

Equal Channel Angular Extrusion ◽

Considerable Change ◽

Fatigue Properties ◽

Dendritic Microstructure ◽

Two Phase ◽

Angular Extrusion ◽

Alloy Increase ◽

The Impact

The mechanical properties mainly tensile properties, impact toughness and high-cycle fatigue properties, of two-phase Al-20Zn alloy subjected to severe plastic deformation (SPD) via equal-channel angular extrusion (ECAE) using route A up to 2 passes were studied. The ECAE almost completely eliminated as-cast dendritic microstructure including casting defects such as micro porosities. A refined microstructure consisting of elongated micro constituents, α and α+η eutectic phases, formed after ECAE via route A. As a result of this microstructural change, mechanical properties mainly the impact toughness and fatigue performance of the as-cast Al-20Zn alloy increased significantly through the ECAE. The rates of increase in fatigue endurance limit are approximately 74 % after one pass and 89 % after two passes while the increase in impact toughness is 122 %. Also the yield and tensile strengths of the alloy increase with ECAE. However, no considerable change occurred in hardness and percentage elongation of the alloy. It was also observed that the ECAE changed the nature of the fatigue fracture characteristics of the as-cast Al-20Zn alloy.

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Physical Simulation of Weldability of Weldox 1300 Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.762.551 ◽

2013 ◽

Vol 762 ◽

pp. 551-555 ◽

Cited By ~ 3

Author(s):

Marek Stanislaw Węglowski ◽

Marian Zeman ◽

Miroslaw Lomozik

Keyword(s):

Mechanical Properties ◽

Impact Toughness ◽

Physical Simulation ◽

High Strength ◽

Parent Material ◽

Cooling Time ◽

Electron Microscopies ◽

Transmission Electron ◽

Transformation Diagrams ◽

The Impact

In the present study, the investigation of weldability of new ultra-high strength - Weldox 1300 steel has been presented. The thermal simulated samples were used to investigate the effect of welding cooling time t8/5 on the microstructure and mechanical properties of the heat affected zone (HAZ). In the frame of these investigation the microstructure was studied by the light (LM) and transmission electron microscopies (TEM). It has been shown that the microstructure of the Weldox 1300 steel is composed of tempered martensite, and inside the laths the minor precipitations mainly V(CN) and molybdenum carbide Mo2C were observed. Mechanical properties of parent material were analysed by the tensile, impact and hardness tests. In details the influence of cooling time in the range of 2,5 - 300 s. on hardness, impact toughness and microstructure of simulated HAZ was studied by using welding thermal simulation test. The results show that the impact toughness and hardness decrease with the increase of t8/5 under the condition of a single thermal cycle in simulated HAZ. The continuous cooling transformation diagrams (CCT-W for welding conditions) of Weldox 1300 steel for welding purposes was also elaborated. The steel Weldox 1300 for cooling time in the range of 2,5 - 4 s showed martensite microstructure, for time from 4 s to 60 s mixture of martensite and bainite, and for longer cooling time mixture of ferrite, bainite and martensite. The results indicated that the weldability of Weldox 1300 steel is limited and to avoid the cold cracking the preheating procedure or medium net linear heat input should be used.

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Influence of Vanadium on the Microstructure and Mechanical Properties of Medium-Carbon Steels for Wheels

Metals ◽

10.3390/met8120978 ◽

2018 ◽

Vol 8 (12) ◽

pp. 978 ◽

Cited By ~ 4

Author(s):

Pengfei Wang ◽

Zhaodong Li ◽

Guobiao Lin ◽

Shitong Zhou ◽

Caifu Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Toughness ◽

Grain Refinement ◽

Carbon Steels ◽

Precipitation Strengthening ◽

Austenite Grain Size ◽

Medium Carbon ◽

Microstructure And Mechanical Properties ◽

Medium Carbon Steels ◽

The Impact

Steels used for high-speed train wheels require a combination of high strength, toughness, and wear resistance. In 0.54% C-0.9% Si wheel steel, the addition of 0.075 or 0.12 wt % V can refine grains and increase the ferrite content and toughness, although the influence on the microstructure and toughness is complex and poorly understood. We investigated the effect of 0.03, 0.12, and 0.23 wt % V on the microstructure and mechanical properties of medium-carbon steels (0.54% C-0.9% Si) for train wheels. As the V content increased, the precipitation strengthening increased, whereas the grain refinement initially increased, and then it remained unchanged. The increase in strength and hardness was mainly due to V(C,N) precipitation strengthening. Increasing the V content to 0.12 wt % refined the austenite grain size and pearlite block size, and increased the density of high-angle ferrite boundaries and ferrite volume fraction. The grain refinement improved the impact toughness. However, the impact toughness then reduced as the V content was increased to 0.23 wt %, because grain refinement did not further increase, whereas precipitation strengthening and ferrite hardening occurred.

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Characteristics and mechanical properties changes due to incorporation of aloe vera in polyethylene-based film

Scientific Research Journal ◽

10.24191/srj.v17i2.9837 ◽

2020 ◽

Vol 17 (2) ◽

pp. 61

Author(s):

Siti Fatma Abd Karim ◽

Junaidah Binti Jai ◽

Ku Halim Ku Hamid ◽

Abdul Wafi Abdul Jalil

Keyword(s):

Mechanical Properties ◽

Thermal Degradation ◽

Aloe Vera ◽

Functional Materials ◽

Chain Structure ◽

Substantial Effect ◽

Scanning Calorimetry ◽

Degradation Temperature ◽

And Performance ◽

The Impact

Non-degradable properties of polyethylene (PE) films due to long-chain structure cause increment of solid waste plastic. Many researchers, with different purposes, have studied the incorporation of functional materials to PE. Studying the impact of incorporation of aloe vera (AV) into PE films in terms of its characteristic and mechanical properties is the main objective of this paper. The films were prepared using melt-blending and hot press technique. The characterization assessed for the PE and PE-AV films were spectroscopy, crystalline phase, thermal analysis and performance of mechanical properties of the sample. The functional group detected in spectroscopy studied did not show any changes for PE film or PE with the presence of AV. Lower thermal degradation temperature (Td) obtained for PE-AV3 while others film found no significant changes of Td value and only one peak of thermal degradation occurred for all film. The same goes to the analysis obtained from differential scanning calorimetry (DSC) data. However, the crystalline structure displayed momentous peak changes for PE with AV. The highest tensile strength (TS) obtained by PE-AV3, at once developing highest value of Young’s modulus (YM), modulus of resilience (UE) and modulus of toughness (UT). A certain amount of AV has substantial effect on changing the polymeric structure especially improving the mechanical properties of PE film. Therefore, AV has potential to become an additive for developing a new partially degradable PE film.

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Ultrasonic Vibration-Assisted Laser Engineered Net Shaping of Inconel 718 Parts: Microstructural and Mechanical Characterization

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4039441 ◽

2018 ◽

Vol 140 (6) ◽

Cited By ~ 17

Author(s):

Fuda Ning ◽

Yingbin Hu ◽

Zhichao Liu ◽

Xinlin Wang ◽

Yuzhou Li ◽

...

Keyword(s):

Mechanical Properties ◽

Ultrasonic Vibration ◽

Inconel 718 ◽

High Efficiency ◽

Experimental Investigations ◽

Laser Engineered Net Shaping ◽

Average Grain Size ◽

Fabrication Defects ◽

Heterogeneous Microstructures ◽

Net Shaping

Laser engineered net shaping (LENS) has become a promising technology in direct manufacturing or repairing of high-performance metal parts. Investigations on LENS manufacturing of Inconel 718 (IN718) parts have been conducted for potential applications in the aircraft turbine component manufacturing or repairing. Fabrication defects, such as pores and heterogeneous microstructures, are inevitably induced in the parts, affecting part qualities and mechanical properties. Therefore, it is necessary to investigate a high-efficiency LENS process for the high-quality IN718 part fabrication. Ultrasonic vibration has been implemented into various melting material solidification processes for part performance improvements. However, there is a lack of studies on the utilization of ultrasonic vibration in LENS process for IN718 part manufacturing. In this paper, ultrasonic vibration-assisted (UV-A) LENS process is, thus, proposed to fabricate IN718 parts for the potential reduction of fabrication defects. Experimental investigations are conducted to study the effects of ultrasonic vibration on microstructures and mechanical properties of LENS-fabricated parts under two levels of laser power. The results showed that ultrasonic vibration could reduce the mean porosity to 0.1%, refine the microstructure with an average grain size of 5 μm, and fragment the detrimental Laves precipitated phase into small particles in a uniform distribution, thus enhancing yield strength, ultimate tensile strength (UTS), microhardness, and wear resistance of the fabricated IN718 parts.

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Effect of Tempering Time on Microstructure and Mechanical Properties of SA738 Gr.B Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.1739 ◽

2021 ◽

Vol 1016 ◽

pp. 1739-1746

Author(s):

Yan Mei Li ◽

Shu Zhan Zhang ◽

Zai Wei Jiang ◽

Sheng Yu ◽

Qi Bin Ye ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Toughness ◽

Yield Strength ◽

Microstructure Evolution ◽

Impact Energy ◽

Nuclear Power ◽

Microstructure And Mechanical Properties ◽

The Impact ◽

Tempering Time

The effect of tempering time on the microstructure and mechanical properties of SA738 Gr.B nuclear power steel was studied using SEM, TEM and thermodynamic software, and its precipitation and microstructure evolution during tempering were clarified. The results showed that SA738 Gr.B nuclear power steel has better comprehensive mechanical properties after tempering at 650 °C for 1h. With the extension of the tempering time, M3C transformed into M23C6 with increasing size, which affected the yield strength and impact energy. When the tempering time is 8h ~ 10h, due to the transformation of M3C to M23C6, the composition of matrix around the carbide changed, causing the temperature of Ac1 dropped, forming twin-martensite which deteriorated the impact toughness of the steel.

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