scholarly journals Microwave Curing Characteristics of CFRP Composite Depending on Thickness Variation Using FBG Temperature Sensors

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1720 ◽  
Author(s):  
Heonyoung Kim ◽  
Donghoon Kang ◽  
Moosun Kim ◽  
Min Hye Jung
Keyword(s):  
Composite Materials ◽  
Thickness Variation ◽  
Specimen Thickness ◽  
Curing Time ◽  
Microwave Curing ◽  
Cure Monitoring ◽  
Curing Characteristics ◽  
Cfrp Composite ◽  
Curing Cycle

Microwave curing technology, which has seen increased commercialization recently due to its ability to cut the curing time and ensure high quality, requires an understanding of the curing characteristics of composite materials of varying thickness. Therefore, this study aimed to perform cure monitoring to evaluate the effects of variations in thickness on the quality of microwave curing. For this study, a fiber Bragg grating sensor was used to measure temperature changes in specimens during the curing cycle for cure monitoring which is generally used for optimization of the curing cycle; then, the time taken for temperature increase and overshoot of the specimen, and the times at which the specimen thickness varied, were quantitatively evaluated. Testing confirmed that microwave curing reduced the curing time in the sections in which the temperature rose; also, the specimen thickness caused overshoot of up to approximately 40 °C at the side, which can affect the curing quality of the composite materials. Furthermore, voids were observed on the side of all specimens. The results indicated that, in order to improve the quality of microwave curing of composite materials, the curing cycle should be optimized by considering the characteristics of the microwave curing equipment.

Energy Intensity and Quality of Recyclate in Composite Recycling

2015 ◽  
Author(s):  
Norshah A. Shuaib ◽  
Paul T. Mativenga
Keyword(s):  
Composite Materials ◽  
Energy Intensity ◽  
Mechanical Performance ◽  
High Demand ◽  
Chemical Methods ◽  
Reinforced Polymer ◽  
Carbon Fibre Reinforced Polymer ◽  
Cfrp Composite ◽  
Fibre Reinforced Polymer

Composite materials are widely used in various sectors such as aerospace, wind energy and automotive. The high demand especially for thermoset based glass (GFRP) and carbon fibre reinforced polymer (CFRP) composite materials has led to a rise in volumes of manufacturing scrap and end-of-life products as composite waste. Unlike thermoplastic polymers, thermoset polymers have difficulties in recycling due to their cross-linked nature. In this paper, thermoset composite recycling processes which are grouped into mechanical, thermal and chemical methods are assessed from the perspectives of energy consumption, processing rate and mechanical performance of the recycled products. The paper presents a benchmark of composite technologies as well as identifies research challenges.

Automation of Microwave Processing of Graphite / Epoxy Composite Materials using an Expert Systems Technique

1992 ◽  
Vol 269 ◽  
Author(s):  
Valerie Adegbite ◽  
Martin Hawley ◽  
Dave Decker ◽  
Jon Sticklen
Keyword(s):  
Composite Materials ◽  
Expert Systems ◽  
Major Elements ◽  
Process Models ◽  
Thermal Curing ◽  
Monitoring And Control ◽  
Microwave Curing ◽  
Selective Heating ◽  
Cure Monitoring ◽  
And Control

ABSTRACTMicrowave curing of composite materials is a novel technology which can be an alternative to conventional thermal curing and has many advantages over thermal curing, i.e, fast and direct heating, selective heating, and controllability. Currently, the existing technology is more empirical and cannot be easily described by traditional process models. One key enabling step for realizing the advantages of the microwave curing technology is a capability for utilizing all the available existing knowledge in a concise manner. The major elements of a control system which utilizes traditional control techniques and (non-traditional) expert systems techniques in a real time microwave cure monitoring and control is discussed.

Conceptual imposings of quality management of system of production of composite materials for it is rocket the space equipment

2017 ◽  
Vol 14 (4) ◽  
pp. 30-38
Author(s):  
V. G. Isaev ◽  
T. N. Antipova
Keyword(s):  
Composite Materials ◽  
Quality Management ◽  
Evaluation Criteria ◽  
Criteria And Indicators ◽  
Properties Of Materials ◽  
A Priority ◽  
Required Quality

Basic provisions of the concept and methodology of production of composite materials for the missile and space equipment are offered. The system of the purposes realizing the principle of a priority of the purposes of the customer is offered. The system of evaluation criteria and indicators of quality of composite materials the realizing interrelation of requirements of the customer to quality of material and dependence of ensuring the required quality on the used technologies is developed. It is shown that for ensuring quality of composite materials for units and the RKT systems first of all it is necessary development of mathematical dependences of properties of materials on parameters of the technological modes in the conditions of obligatory implementation of requirements of the customer.

Determination of optimal microwave curing cycle for fly ash mortars

2008 ◽  
Vol 35 (4) ◽  
pp. 349-357 ◽  
Author(s):  
İlker Bekir Topçu ◽  
Mehmet Uğur Toprak ◽  
Devrim Akdağ
Keyword(s):  
Fly Ash ◽  
Processing Parameters ◽  
Microwave Energy ◽  
Strength Prediction ◽  
Strength Development ◽  
Microwave Curing ◽  
Optimal Processing ◽  
Cement Mortars ◽  
Curing Cycle

Microwave energy can accelerate the hydration of cement, which results in the rapid strength development of concrete. In this paper, prediction of later age compressive strength of fly ash cement mortars, based on the accelerated strength of mortars cured with microwave energy, was investigated. To accelerate curing properly, optimal processing parameters of microwave curing (MC) on Portland cement mortars (CM) and fly ash cement mortars (FA) were first determined and then were applied to mortars. The possible early ages for the strength prediction were found to be at 6 and 8 h for CM and FA, respectively. The error percentages for prediction of CM were ±2.22% and 2.91% for 7 and 28 d, respectively. Error percentages for FA, on the other hand, were ±4.36% and 5.20% for 7 and 28 d, respectively.

Electromechanical-Conductive Natural Rubber Doped Eggshell and Eggshell Membrane for Drug Delivery and Actuator Applications

2018 ◽  
Vol 934 ◽  
pp. 43-49
Author(s):  
Poramin Boonprasert ◽  
Nuchnapa Tangboriboon
Keyword(s):  
Composite Materials ◽  
Natural Rubber ◽  
Artificial Muscle ◽  
Eggshell Membrane ◽  
Curing Time ◽  
Electrical Field ◽  
Fibrous Protein ◽  
Rubber Composite ◽  
Field Response ◽  
Biomimetic Actuator

Natural rubber composite materials were prepared by using sulfur curing system of STR 5L added with hen eggshell and eggshell membrane to increase electrical and mechanical properties for biomimetic actuator and artificial muscle applications. Samples were vulcanized at temperature 150°C. Hen eggshells and eggshell membrane powder (0, 20, 40, and 60 phr) were added into natural rubber. The main composition of hen eggshells composed of 96.35 wt% calcium carbonate (CaCO3) while mostly composition of hen eggshell membrane is fibrous protein in terms of collagen. The best condition is addition of eggshell 40 phr (formula 3) and eggshell membrane 20 phr (formula 5) to obtain the highest storage modulus response equal to 2.85 x 106 and 2.97 x106 Pa, respectively. The curing time (Tc90) of pure natural rubber (formula 1), formula 3, and formula 5 are 8.22, 6.73, and 5.67 min, respectively. Furthermore, the curing time, rheology, and electrical field response of natural rubber composite materials were measured by moving die rheometer and impedance analyzer, and reported here.

scholarly journals Study of clay minerals effect on curing characteristics of polymer blends and physical-mechanical properties of prepared vulcanizates

2018 ◽  
Vol 157 ◽  
pp. 07010
Author(s):  
Beáta Pecušová ◽  
Mariana Pajtášová ◽  
Zuzana Mičicová ◽  
Darina Ondrušová ◽  
Andrea Feriancová ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Polymer Blends ◽  
Clay Minerals ◽  
Structural Type ◽  
Partial Replacement ◽  
Curing Characteristics ◽  
Dioctahedral Smectite ◽  
The Common ◽  
The Given

The given paper deals with the study of the properties of clay minerals, namely montmorillonite and moreover, it is focused on effect of these clay minerals on the curing characteristics of the polymer blends and the physical-mechanical properties of prepared vulcanizates. Montmorillonite is a major clay mineral which has a wide application in many industrial branches. It belongs to the group of dioctahedral smectite minerals with structural type in the ratio of 2:1. Characteristics of prepared modified and organomodified clay minerals are based on sulphur vulcanisation accelerators which are used for the preparation of real polymer blend where they represent a partial replacement of the common carbon black filler and then, the effect on the curing characteristics of polymer blends as well as physical-mechanical properties of the prepared vulcanizates are investigated. The results exhibit that the clay-based filler (modified and organomodified clay minerals) can be used as a partial replacement while the quality of the prepared blends is preserved.

scholarly journals Effect of Post-Process Curing and Washing Time on Mechanical Properties of mSLA Printouts

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4856
Author(s):  
Bartłomiej Nowacki ◽  
Paweł Kowol ◽  
Mateusz Kozioł ◽  
Piotr Olesik ◽  
Jakub Wieczorek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Curing Time ◽  
Cross Sectional ◽  
Post Process ◽  
Order Of Magnitude ◽  
Static Tensile ◽  
High Roughness ◽  
Ambiguous Effect

The article discusses the influence of the post-process on the mechanical properties of elements produced with the use of the mask stereolithography (mSLA) method. Printed samples were subjected to the following post-process steps: Washing and post-curing, at various times. Then, static tensile and static bending tests were carried out, as well as Shore D hardness measurements for the inner and surface part of the sample, as well as profilographometric analysis of the surface. The post-curing time has been found to strongly affect the tensile and bending strength of printouts, and to improve their surface quality. Washing has an ambiguous effect on the strength of the printouts, but, in the end, it was found that extended washing slightly reduces the strength. Washing significantly affects the quality of the printout surface. A washing time that is too short results in a surface that strongly resembles the printing process, with high roughness. Increasing the washing time to 10 min lowers the roughness by one order of magnitude. Post-curing has also been shown to be beneficial for the cured sample with the application of shielding water. This approach results in an improvement in the flexural strength of the printouts. In general, the obtained research results indicate that, for printouts with cross-sectional dimensions of several mm, the optimal washing time is no more than 10 min and the post-curing time is at least 30 min.

scholarly journals Effect of Light-Sources and Thicknesses of Composite Onlays on Micro-Hardness of Luting Composites

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6849
Author(s):  
Francesco De Angelis ◽  
Mirco Vadini ◽  
Mario Capogreco ◽  
Camillo D’Arcangelo ◽  
Maurizio D’Amario
Keyword(s):  
High Power ◽  
Resin Composite ◽  
Composite Layer ◽  
Resin Cement ◽  
Specimen Thickness ◽  
Light Sources ◽  
Curing Time ◽  
Resin Cements ◽  
Halogen Light ◽  
Light Curing

The aim of this study was to compare three different light-curing-units (LCUs) and determine their effectiveness in the adhesive cementation of indirect composite restorations when a light-curing resin cement is used. Two resin composites were selected: Enamel Plus HRI (Micerium) and AURA (SDI). Three thicknesses (3 mm, 4 mm and 5 mm) were produced and applied as overlays and underlays for each resin composite. A standardized composite layer was placed between underlay and overlay surfaces. Light curing of the resin-based luting composites was attained through the overlay filters using LCUs for different exposure times. All specimens were allocated to experimental groups according to the overlay thickness, curing unit and curing time. Vickers Hardness (VH) notches were carried out on each specimen. Data were statistically evaluated. The curing unit, curing time and overlay thickness were significant factors capable of influencing VH values. The results showed significantly decreased VH values with increasing specimen thickness (p < 0.05). Significant differences in VH values were found amongst the LCUs for the various exposure times (p < 0.05). According to the results, a time of cure shorter than 80 s (with a conventional quartz–tungsten–halogen LCU) or shorter than 40 s (with a high-power light-emitting diode (LED) LCU) is not recommended. The only subgroup achieving clinically acceptable VH values after a short 20 s curing time included the 3 mm-thick overlays made out of the AURA composite, when the high-power LED LCU unit was used (VH 51.0). Composite thickness has an intense effect on polymerization. In clinical practice, light-cured resin cements may result in insufficient polymerization for high thickness and inadequate times. High-intensity curing lights can attain the sufficient polymerization of resin cements through overlays in a significantly shorter time than conventional halogen light.

scholarly journals AKSEPTABILITAS DAN SIFAT DAGING ITIK AFKIR YANG DILAKUKAN CURING MENGGUNAKAN EKSTRAK KURKUMIN KUNYIT UNTUK MENGHAMBAT OKSIDASI LEMAK SELAMA PENYIMPANAN

2015 ◽  
Vol 34 (04) ◽  
pp. 415 ◽  
Author(s):  
Sri Hartati Candra Dewi ◽  
Niken Astuti
Keyword(s):  
Fatty Acids ◽  
Peroxide Value ◽  
Frozen Storage ◽  
Oxidation Potential ◽  
Curing Time ◽  
Turmeric Extract ◽  
Randomized Design ◽  
Fatty Acid Peroxidation ◽  
Age Range

Rejected-duck meat was obtained from old laying duck that unproductive aged 24-26 months. The purpose of this study was to determine the oxidation potential of curcumin extract and its potential in curing rejects the acceptability of duck meat and meat properties during frozen storage. The material used was 36 female rejected-duck the age range 24-26months. The experimental design used was completely randomized design with 3x4 factorial variation. This factor of 0.0 %; 0.1 % ; 0.2 % and 0.3 % curcumin extract and the curing time 5, 10 and 20 minutes. The parameters examined included the acceptability of duck meat cured was determined by the method of Hedonic Test, moisture content , fatcontent, fatty acids and peroxide value of frozen storage for 8 weeks. The results showed that duck meatwas acceptable salvage most of duck meat with curing using 0.3 % turmeric extract with a curing time for 10 minutes. The addition of curcumin turmeric extract the meat of rejected-ducks could inhibit fatty acid peroxidation approximately 39.55 m.eq in frozen storage for five weeks. Water content and fat showed no real difference. However, free fatty acids increased significantly up to 5 weeks. Peroxide value increased until the fifth week of 39.55 %, and then decreased. From thisstudy it can be concluded that the best use extract acceptability of curcumin 0.3 % with long curing 10 minutes, the frozen storagefor8weeks.Keywords: Rejected- ducks meat, curcumin, antioxidant, acceptability and quality of the meat ABSTRAKDaging itik afkir diperoleh dari itik petelur yang sudah tidak produktif yang berumur 24-26 bulan. Tujuan penelitian ini adalah untuk mengetahui potensi oksidasi dari ekstrak kurkumin dan potensinya dalam curing daging itik afkir terhadap akseptabilitas dan sifat daging selama penyimpanan beku.Materi yang digunakan 36 ekor itik betina afkirdengan kisaran umur 24-26 bulan. Rancangan percobaan yang digunakan adalah rancangan acak lengkap pola faktorial 3x4 dengan faktor variasi ekstrak kurkumin 0,0%; 0,1%; 0,2% dan 0,3% dan lama curing 5, 10 dan 20 menit. Parameter yang diteliti meliputi akseptabilitas daging itik curing ditentukan dengan metode Hedonic Test, kadar air, kadar lemak,asam lemak dan angka peroksida penyimpanan beku selama 8 minggu. Hasil penelitian menunjukkan bahwa daging itik afkir yang paling akseptabel adalah daging itik dengan curing menggunakan 0,3% ekstrak kunyit dengan lama curing selama 10 menit. Penambahan ekstrak kurkumin kunyit pada daging itik afkir mampu menghambat peroksidasi asam lemak sekitar 39,55% pada penyimpanan beku selama lima minggu. Kadar air dan lemak menunjukkan perbedaan yang tidak nyata. Namun asam lemak bebas mengalami kenaikan yang signifikan sampai minggu ke 5. Angka peroksida meningkat sampai minggu kelima sebesar 39,55 m.eq, kemudian menurun. Dari penelitian ini dapat disimpulkan bahwa akseptabilitas terbaik menggunakan ekstrak kurkumin 0,3% dengan lama curing 10 menit, pada penyimpanan beku selama 8 minggu.Kata kunci:Daging itik afkir, antioksidan kurkumin, akseptabilitas dan kualitas daging

scholarly journals Cutting mode impact upon output process parameters at processing of polycrystalline composite materials

2017 ◽  
Vol 2 (6) ◽  
pp. 34-38
Author(s):  
Ю. Зубарев ◽  
Yu. Zubarev ◽  
А. Приемышев ◽  
A. Priyomyshev ◽  
А. Заостровский ◽  
...  
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Process Parameters ◽  
Polymeric Composite ◽  
Polymeric Composite Material ◽  
Output Process ◽  
Product Surface ◽  
Required Quality ◽  
Material Cutting

The peculiarities in polymeric composite material cutting are considered. The recommendations for use of different materials for cutters, their geometry and treatment modes are offered that allows obtaining the required quality of a product surface.

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