Browsing NTNU Open by Author "Echtermeyer, Andreas"
Now showing items 41-60 of 91
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Immersed interlaminar fatigue of glass fiber epoxy composites using the I-beam method
Gagani, Abedin; Mialon, Emeric; Echtermeyer, Andreas (Journal article; Peer reviewed, 2019)Exposure to marine environment causes a degradation of the interlaminar shear performance of composites. This effect has been reported in several studies, but the mechanisms that lead to failure in composites subjected to ... -
In-Situ Strain Measurements in Large Volumes of Hardening Epoxy Using Optical Backscatter Reflectometry
Heinze, Søren; Echtermeyer, Andreas (Journal article; Peer reviewed, 2018)Some large engineering structures are made by casting polymers into a mold. The structures can have complicated geometries and may be filled with other components, such as electrical transformers. This study investigated ... -
Influence of Compounding Parameters on the Tensile Properties and Fibre Dispersion of Injection-Moulded Polylactic Acid and Thermomechanical Pulp Fibre Biocomposites
Zarna, Chiara; Rodriguez-Fabia, Sandra; Echtermeyer, Andreas; Chinga-Carrasco, Gary (Peer reviewed; Journal article, 2022)Thermomechanical pulp (TMP) fibres can serve as renewable, cost-efficient and lightweight reinforcement for thermoplastic polymers such as poly(lactic acid) (PLA). The reinforcing ability of TMP fibres can be reduced due ... -
Influence of delaminations on fluid diffusion in multidirectional composite laminates – Theory and experiments
Gagani, Abedin; Echtermeyer, Andreas (Journal article; Peer reviewed, 2018)Multidirectional composite laminates are often used in marine and offshore applications. Upon cyclic loading, cracks appear early in the off-axis plies and generate delaminations, which accelerate fluid diffusion. In this ... -
Innovative Impact Protection and Monitoring System for Composite Pressure Vessels
Kopperud, Paul Andreas (Master thesis, 2015)Impact behavior and resistance of composite structures are difficult to predict. For composite pressure vessels, where failure can be fatal, impact protection and detection is particularly important. This thesis aims to ... -
Integration and performance of distributed optical fibre sensors in thermoplastics and thermoplastic composites
Wang, Shaoquan (Doctoral theses at NTNU;2023:129, Doctoral thesis, 2023)Today, thermoplastics and fibre reinforced thermoplastic composites, are increasingly being used in all fields of commerce and industry, for their improved performance with respect to impact resistance, recyclability, and ... -
Interfacial leakage of elastomer seals at low temperatures
Akulichev, Anton; Echtermeyer, Andreas; Persson, B. N. J (Journal article; Peer reviewed, 2018)Interfacial leakage of air in hydrogenated nitrile butadiene rubber (HNBR) O-ring seals exposed to sub-ambient temperatures is studied. Flange-type fixtures with sealing surfaces produced by 3 different surface finish ... -
Long Term Degradation of Polymers: Molecular and Macroscopic Effects
Berggren, Randi (Master thesis, 2013)Hydrolytic degradation in water at elevated temperatures is one of the most important reasons for failure in polymeric materials in offshore flexible risers. In this thesis the ageing of polyamide 11 (PA11) in deoxygenated ... -
Long term material properties of pressure vessels made of composite material
Hugaas, Eivind (Doctoral theses at NTNU;2022:56, Doctoral thesis, 2022)Pressure vessels are currently the limiting factor in the hydrogen distribution chain. The pressure vessels are preferably made out of composite materials to achieve practical weight to strength ratios and avoid hydrogen ... -
Long Term Properties of Composites and Polymers
Arun, Adithya (Master thesis, 2023)Kompositt- og polymermaterialer brukes i offshore og maritim industri, men data angående deres ytelse etter langvarig eksponering for miljøet er begrenset. Dette er hovedsakelig på grunn av mangel på testede data vedrørende ... -
Long Term Properties of Glass Fiber Epoxy Laminates in Dry and Humid Environment
Hagen, William Eik (Master thesis, 2022)A study of the stress rupture time of glass fiber epoxy composite laminates in humid environments was investigated. Test specimens were made in order to compare the failure time of a saturated and non-saturated specimen ... -
Long-Term Dissolution of Glass Fibers in Water Described by Dissolving Cylinder Zero-Order Kinetic Model: Mass Loss and Radius Reduction.
Krauklis, Andrey; Echtermeyer, Andreas (Journal article; Peer reviewed, 2018)Glass fibers are degraded when they are exposed to water. In this work, a model is developed that uses zero-order kinetics for predicting a decreasing glass fiber radius. The model is used to describe experimental test ... -
Long-Term Hydrolytic Degradation of the Sizing-Rich Composite Interphase
Krauklis, Andrey; Gagani, Abedin; Echtermeyer, Andreas (Journal article; Peer reviewed, 2019)Glass fiber-reinforced composites are exposed to hydrolytic degradation in subsea and offshore applications. Fiber-matrix interphase degradation was observed after the matrix was fully saturated with water and typical water ... -
Long-term ISO 23936-2 sweet oil ageing of HNBR
Akulichev, Anton; Alcock, Benjamin; Krauklis, Andrey; Tiwari, Avinash; Echtermeyer, Andreas (Journal article; Peer reviewed, 2021)A hydrogenated nitrile butadiene rubber (HNBR) compound is subjected to ageing in a simulated oil and gas environment in accordance with ISO 23936-2 standard at two elevated temperatures (130 °C and 150 °C) for a period ... -
Long-Term Properties of Interlaminar Shear Strength of Composite Laminates
Monsås, Anna Birgitte (Master thesis, 2018)Components made of fiber reinforced polymers (FRP) are frequently used in environments with fluctuating temperatures and moisture levels. These environmental factors lead to a degradation of the FRP in the long term. The ... -
Long-term properties of the matrix of composites
Næss, Christoffer (Master thesis, 2016)Water diffusion into epoxy can be looked upon on as a 3-stage process. The first stage is the initial reaction, where the ends and available surfaces of the molecular chains bond with the water molecules. These easily ... -
Mechanical and Thermal Simulations of 3D Printed Structures and the 3D Printing Process
Ramos, Nathalie (Doctoral theses at NTNU;2023:311, Doctoral thesis, 2023)Additive manufacturing (AM), often referred to as three-dimensional (3D) printing, has become one the fastest growing manufacturing technologies across a variety of engineering fields after transitioning from being a ... -
Mechanical Properties of Elastomers at Low Temperatures for Sealing Applications
Vestre, Andreas (Master thesis, 2015)With increased oil and gas activity in low-temperature areas of the world, it is highly important that the industry utilize the most robust materials and zero-leakage solutions. The O ring is a type of elastomer sealer ... -
Mechanical Properties of Elastomers at Low Temperatures for Sealing Applications
Vestre, Andreas (Master thesis, 2015)With increased oil and gas activity in low-temperature areas of the world, it is highly important that the industry utilize the most robust materials and zero-leakage solutions. The O ring is a type of elastomer sealer ... -
Mechanism of Yellowing: Carbonyl Formation during Hygrothermal Aging in a Common Amine Epoxy
Krauklis, Andrejs; Echtermeyer, Andreas (Journal article; Peer reviewed, 2018)Epoxies are often exposed to water due to rain and humid air environments. Epoxy yellows during its service time under these conditions, even when protected from UV radiation. The material’s color is not regained upon ...