Tekstil-Giyim-Ayakkabı-Deri Bölümü

Bu koleksiyon için kalıcı URI

https://hdl.handle.net/20.500.12491/10796

Listeleniyor 1 - 12 / 12

Biobased hybrid composite design for optimum hardness and wear resistance
(Elseiver, 2023) Okafor, Christian Emeka; Sunday, Iweriolor; Ani, Okwuchukwu Innocen; Akçakale, Nürettin; Ekwueme, Godspower Onyekachukwu; Ugwu, Peter Chukwuemeka; Nwanna, Emmanuel Chukwudi
The present investigation considered the design of a biobased hybrid particulate composite for optimal hardness and wear resistance. Tests were conducted based on the plan of 20 sets of experiments generated through ModelBased Calibration ToolboxTM contained in MATLAB routines. A Portable Ultrasonic Hardness tester was used to record the hardness properties while the wear behavior of the composite was tested using a pin-on-disk machine. The optimization study was applied to the Calibration Generation (CAGE) platform utilizing the Normal Boundary Intersection (NBI) algorithm which enables the development of a Pareto optimal set with a continuous and equally distributed chart. Scanning Electron Microscopy (SEM) was used to perform morphological examination. From the optimized results, it was observed that a particle size of 1752 mu m, a volume fraction of 45%, and a stirring time of 70 s gave the best-ranked composite exhibiting optimal values of 784.91 Leeb hardness, 643.19 Rockwell hardness, 593.17 Brinell hardness, and 0.000139 mm3/Nm specific wear rate. Under the same conditions, the predicted values of the optimization model closely matched the experimental results. The NBI optimization technique proves to be a viable method for performing material design and property improvement tasks. Surface morphology analysis via SEM revealed that the wearing of bio-based hybrid particulate composite parts is associated with delamination and abrasion mechanisms. It is implied that the new material can be used for applications such as furniture, automotive spare parts, and other inexpensive technical solutions.
The effect of wood ash on the mechanical properties of rubber compounds
(Inst Za Kovinske Materiale I In Tehnologie, 2019) Bülbül, Saban; Akçakale, Nürettin; Yaşar, Mustafa; Gökmeşe, Hakan
In this study, the effect of adding wood ash (oak tree) on the mechanical properties (tensile, abrasion, tearing, elongation %, etc.) of NR/SBR-type elastomer materials was investigated. Five different compounds were prepared by adding 16 %, 32 %, 48 % and 64 % wood ash to the filler and additive materials in the general composition (G). The mechanical test results and production costs of the new compounds composed were compared between themselves and with the G compound. The fracture surfaces of the compounds as well as the shape and morphological distribution of the fillers in the rubber matrix were examined using a Scanning Electron Microscope (SEM). As a result of the experimental studies, it was found that the new compounds composed had an increased tensile and tearing strength. abrasion amounts, bending capability, unit elongation amounts and densities in comparison to the G compound. A decrease was observed in the hardness values and material costs (production cost) of the compounds.
The effect of mica powder and wollastonite fillings on the mechanical properties of NR/SBR type elastomer compounds
(Rubber Res Inst Malaysia, 2017) Akçakale, Nürettin; Bülbül, Şaban
In this study the effects of wollastonite and mica powder used at different ratios as filler in NR/SBR type elastomer based rubber were examined in terms of ts mechanical properties. Natural rubber (NR/RSS3) and styrene butadiene rubber were used as main matrix material in the experiments. While adhering to the same compound, various amounts of wollastonite (FW 325) and mica powder (Mica SMW 375) were added to the carbon black (HAF N339) and six different compounds were prepared. Properties of the compounds such as tensile strength, elongation at break, abrasion, and hardness were analysed and the test results were compared to each other. In addition, SEM images of the abraded surfaces were evaluated and a brief cost analysis was realised. It is concluded that hardness, density and abrasion loss increased while elongation at break, tensile strength, fatigue resistance and unit cost decreased when the amount of wollastonite and mica powder was increased in the compounds.
Effects of carburized rice husk powders on physical properties of elastomer based materials
(Dr Alfred Huthig Verlag Gmbh, 2017) Akçakale, Nürettin
In this study the effects of carburized rice husk (CRH) powders on the mechanical properties of SBR (SBR 1502) / waste rubber type elastomer based materials were investigated. In addition to the calcite and rubber powder fillings in the general composition of a rubber formula used in footwear production, CRH obtained by the Proliz method were added at 5-10-15-20% ratios and new compounds were formed. The hardness, density, wearing rate, breaking strength, percentage elongation amount and tear strength values of the new compounds obtained were compared with both the original formula and with each other. The test results of the new compounds obtained show an increase in hardness, density and wear when compared to the general formula.
Conductivity mechanism of mica powders inlaid elastomer based materials
(Elsevier Science Sa, 2016) Şentürk, Erdoğan; Akçakale, Nürettin; Okutan, Mustafa
In this study, electrical properties of mica powder inlaid NR/SBR type elastomer based rubber material have been investigated by dielectric spectroscopy. Electrical modulus of this sample showed dispersion in the frequency range investigated, especially in the lower frequency region of the dispersion curve showing long distance conductivity for the charge carriers. DC conductivity curve exhibits that glass transition temperature is around 350 K. AC conductivity behavior supports the Correlated Barrier Hopping mechanism. (C) 2016 Elsevier B.V. All rights reserved.
Effect of changing of filling materials in NR-SBR type elastomer based rubber materials on mechanical properties
(Polymer Soc Korea, 2014) Bülbül, Şaban; Yaşar, Mustafa; Akçakale, Nurettin
The effects of different filling materials and stabilizers in polymer based materials that are used as shoe soles in the shoemaking industry on the mechanical properties (strength, failure, tensile, tearing, bending etc.) of the final products have been examined in this study. Natural rubber (NR RSS3) and styrene-butadiene rubber (SBR 1502) were used as the main matrix material. New compounds were formed by replacing the fillings in the general compound of the existing factory (SiO2, CaCO3) with 40% (1200 g) blast furnace flue dust, rice husk, reclaimed rubber (recycled) and wood ash. Comparison of the new compounds with the existing compounds revealed a decrease in hardness, density, dimension stability, bending, tearing, % elongation and failure strength and an increase in wearing.
OLPT conductivity in Wolastonite inlaid NR/SBR type elastomer based material
(Univ Chemistry & Technology, Prague, 2012) Şentürk, Erdoğan; Yüksel, T.; Okutan, Mustafa; Demirer, Ahmet; Akçakale, Nurettin
The electrical properties of wollastonite inlaid NR/SBR type elastomer based material have been evaluated. Electrical properties of the samples were measured in the temperature range of 303 to 453 K and the frequency range of 100 Hz - 40 MHz. All electrically measured parameters were given anomalies at 385 K. Only one type of dielectric relaxation process have been observed for all measurements. Physical parameters characterizing the dielectric behavior have been obtained by fitting the experimental results in the modified Debye equation. The activation energy which is thermally activated by dielectric relaxation process have been calculated to be 0.58 eV. DC conductivity increasing by temperature has been explained with the help of VFT model whereas the AC one has been clarified by the OLPT model.
Effects of glass spheres on the mechanical characteristics of NR-SBR type elastomers
(Academic Journals, 2010) Akçakale, Nürettin; Demirer, Ahmet; Nart, E.; Özsert, İbrahim
In this study, the effect of glass spheres on the physical and mechanical properties of NR-SBR elastomer-based shoe sole material was investigated. In the experiment, the blend of natural rubber (NR-RSS3) and styrene butadiene rubber (SBR 1502) in certain amounts were considered to use. Therefore, 2 newly developed glass sphere blends were prepared and tested. The new blends exhibited much better mechanical properties than the traditional ones. The results showed that glass spheres between 5 -13.5% in the new blends resulted in 23 to 31% decrease in the material cost. Additionally, the new blends exhibited higher mechanical properties compared to that of traditional ones.
Determination of the VOCs by headspace methods in leather production process
(Chinese Leather Industry Assoc, 2009) Akyüz, Fazlı; Sarı, Özcan
In this study, the components which will cause emissions in the old tanning industry were determined, and the processes as potential polluting were shown. Twenty sheepskins from a facility of meat and meat products located in Izmir were processed with a typical clothing sheepskin recipe. Samples were taken from certain production steps and analysed according to Headspace-GC/FID/MS and GC-FID-MS for the volatile organic compounds. This study also evaluated the production steps which will cause emission problems.
Odor: An important problem in leather industry
(Deri Teknologlari, Teknisyenleri ve Kimyacilari Dernegi, 2013) Akyüz, Fazlı
One of the most important indications that announce the availability of the leather industry to the environment is odour. Addition to odours released as a result of both raw skins and hides are organic materials, and chemical reactions occurred between chemicals used in processing and leather, some odours is also to spread from waste water treatment facilities. All over the world, odour is one of the problems that are mostly complained to the environmentalist foundations and organizations.
Surface area gain of leathers dried under different conditions
(CSIR-CLRI, 2017) Karavana, Hüseyin Ata; Kılınç, Kemal
Drying is one of the most important leather production processes which is necessary to obtain usable leather form from skin and determines the basic structural, chemical and physical properties of the leather. Using different drying methods in the footwear upper production affect the change in surface area of the leathers as distinct from each other. Surface area gain has a great significance since the footwear upper leathers are sold depend their size of the surface area. In this research, it is determined that the surface area gain of the each footwear upper leathers which manufactured using the wet-toggle and vacuum drying methods that are different drying processes, and the area gain of the leathers are compared. As a result, it is observed that the significance changes occurred on the surface area gain of the same origin upper leathers as using the different drying methods and conditions. Especially, the wet-toggle for the drying of footwear upper leathers is a preferable drying method because of the better surface area gain provided by the method.
Tunability properties of mica powders inlaid nr/sbr material
(2016) Kuru, Tuğba Şaşmaz; Akçakale, Nürettin
NR (natural rubber) and SBR (synthetic rubber) elastomers are have in a wide range of applications due to their interesting properties. These are primarily in the automotive, aerospace, machinery manufacturing, construction and shoe industry [1,2]. NR/SBR based materials have increasingly attention with some different additions. In this study, dielectric tunability properties of the mica powder inlaid NR/SBR elastomer have been by using dielectric spectroscopy. The dielectric constant of the sample has been measured by using a LCR meter in the interval of 0-2500 V/m electric field. The measurements have been carried out at some fixed frequencies starting from 100 Hz. The dielectric constant depends on frequency and applied electric field. It decreases with the increase of frequency and applied field. The decreasing proportion of the dielectric constant with applied field decreases with increasing frequency. Finally, it is constant with applied field at high frequencies. The properties of the sample have been explained with tunability properties of the sample.

Güncel Gönderiler