Mechanical performance of composite flat specimens and pressure vessels produced by carbon/epoxy towpreg dry winding

Date

2022-10-01

Author

Okten, Yigit Kemal
Kaynak, Cevdet

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

189
views

0
downloads

The main purpose of this study is to evaluate the effects of certain processing parameters on the mechanical performance of carbon/epoxy towpreg wound composite structures. For this purpose, composite sample productions and their evaluations were conducted in two steps. In the first step, dry winding of carbon/epoxy towpregs was used to produce flat composite plates. Their evaluation was performed by rheological analysis, interlaminar shear tests, and unidirectional tensile tests. In the second step, towpreg dry winding was used to produce composite pressure vessel samples. Their performance was evaluated by observing the effects of various winding process parameters on the safety of the vessels via hydrostatic burst pressure tests. Compared to the traditional wet filament winding, the main difficulty observed was maintaining the "straight towpreg path" necessary for efficient winding operations. This problem was prevented by applying higher tension forces during dry winding. Evaluation of the hydrostatic burst tests in terms of burst pressure, hoop strain and safe failure mode revealed that the optimum pressure vessel performance could be obtained in the vessel samples with "helical-hoop-helical winding layer sequence." On the other hand, use of "complex helical pattern" resulted in no advantages at all, due to basically higher number of undulation zones acting as stress concentration zones.

Subject Keywords

Carbon, epoxy towpreg, wet filament winding, dry winding, hydrostatic burst pressure, mechanical properties, STACKING-SEQUENCE, FILAMENT, PARAMETERS, STRENGTH, FAILURE, PATTERNS, BEHAVIOR

URI

https://hdl.handle.net/11511/100437

Journal

JOURNAL OF REINFORCED PLASTICS AND COMPOSITES

DOI

https://doi.org/10.1177/07316844221134029

Collections

Department of Metallurgical and Materials Engineering, Article

Suggestions

OpenMETU
Core

Use of carbon/epoxy towpregs during dry filament winding of composite flat specimens and pressure vessels Ökten, Yiğit Kemal; Kaynak, Cevdet; Department of Metallurgical and Materials Engineering (2022-6-28) The main purpose of this thesis is to evaluate the effects of certain processing parameters on the performance of carbon/epoxy towpreg wound composite structures. For this purpose, composite sample productions and their evaluations were conducted in two steps. In the first step, dry winding of carbon/epoxy towpregs was used for the production of flat composite plates. Their evaluation was performed by rheological analysis, interlaminar shear tests and unidirectional tensile tests. In the second step, towpre...
Transient dynamic response of viscoelastic cylinders enclosed in filament wound cylindrical composites Şen, Özge; Turhan, Doğan; Department of Engineering Sciences (2005) In this study, transient dynamic response of viscoelastic cylinders enclosed in filament wound cylindrical composites is investigated. Thermal effects, in addition to mechanical effects, are taken into consideration. A generalized thermoelasticity theory which incorporates the temperature rate among the constitutive variables and is referred to as temperature-rate dependent thermoelasticity theory is employed. This theory predicts finite heat propagation speeds. The body considered in this thesis consists o...
Thermal stress intensity factor evaluation for inclined cracks in functionally graded materials using Jk-integral method Demirçivi, Bengi; Dağ, Serkan; Department of Mechanical Engineering (2006) The main objective of this study is to evaluate mixed mode stress intensity factors for inclined embedded cracks in functionally graded materials. Fracture analysis of inclined cracks requires the calculation of both Mode I and Mode II stress intensity factors ( I K , II K ). In this study, k J -integral is used to calculate I K and II K . Equivalent domain integral approach is utilized to evaluate the k J - integral around the crack tip. The present study aims at developing a finite element model to study ...
Comparison of magnetic Barkhausen noise and ultrasonic velocity measurements for microstructure evaluation of SAE 1040 and SAE 4140 steels Gür, Cemil Hakan; Çam, İbrahim (Elsevier BV, 2007-05-01) The aim of this study is to compare the performance of magnetic Barkhausen noise and ultrasonic methods for the evaluation of the microstructure of commercial steels. Following the austenitization of the specimens made of SAE 1040 and SAE 4140, various heat treatments were carried out to obtain microstructures consisting of martensite, tempered martensite, fine pearlite-ferrite, and coarse pearlite-ferrite. The microstructures were initially characterized by SEM investigation and hardness measurements. The ...
Development of test structures and methods for characterization of MEMS materials Yıldırım, Ender; Arıkan, Mehmet Ali Sahir; Department of Mechanical Engineering (2005) This study concerns with the testing methods for mechanical characterization at micron scale. The need for the study arises from the fact that the mechanical properties of materials at micron scale differ compared to their bulk counterparts, depending on the microfabrication method involved. Various test structures are designed according to the criteria specified in this thesis, and tested for this purpose in micron scale. Static and fatigue properties of the materials are aimed to be extracted through the ...

Citation Formats

Y. K. Okten and C. Kaynak, “Mechanical performance of composite flat specimens and pressure vessels produced by carbon/epoxy towpreg dry winding,” JOURNAL OF REINFORCED PLASTICS AND COMPOSITES, pp. 0–0, 2022, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/100437.