Search
Now showing items 31-40 of 114
Aufsatz
Enabling magnetic pulse welding for dissimilar tubular arrester cable joints
(2024-04-08)
Climate change exacerbates the need for resource-efficient and cost-effective production processes across manifold industries, including the field of electrical connections. This specific field is characterized by a conflict of objectives, i.e., weight reductions while maintaining joint strength and electrical conductivity. From a material point of view, the use of aluminum as a conductor material is suitable for this application, as it is lighter than copper, a classical conductor material. Electrical conductors are ...
Aufsatz
Dynamic tensile deformation behavior of AISI 316L stainless steel fabricated by laser-beam directed energy deposition
(2023-11-07)
The dynamic deformation behavior of metallic materials is the key to crash-safe design in many applications, e.g., in the automotive sector. However, in the field of additive manufacturing, dynamic deformation properties have only been scarcely studied. Based on the intrinsic interrelationships of process parameters, post-process heat treatments and the resulting microstructure, the present study seeks to provide a holistic overview of the dynamic tensile deformation properties of AISI 316L stainless steel, fabricated ...
Aufsatz
Mathematical modelling of a latent heat storage: Influence of PCM thermal conductivity and enthalpy-temperature relationship
(2024-06-08)
Mathematical modelling of latent heat storage units is useful to calculate their thermal performance for integration in larger systems. This requires the input of thermophysical properties of the phase change material (PCM) used, but data provided by manufacturers or published in the literature is often incomplete and/or varies between sources. However, it is not clear to what extent an accurate knowledge of these properties, including their phase dependency, is necessary to obtain reliable calculations, especially ...
Aufsatz
Mechanical Analysis and Simulation of Wood Textile Composites
(2024-05-18)
Wood Textile Composites (WTCs) represent a new and innovative class of materials in the field of natural fiber composites. Consisting of fabrics made from willow wood strips (Salix americana) and polypropylene (PP), this material appears to be particularly suitable for structural applications in lightweight construction. Since the threads of the fabric are significantly oversized compared to classic carbon or glass rovings, fundamental knowledge of the mechanical properties of the material is required. The aim of ...
Aufsatz
Self-generation and outage losses: A firm-level analysis for emerging and developing Asian countries
(2024-02-26)
Access to reliable and affordable electricity is critical to economic development in emerging and developing Asia. However, many firms in these regions face challenges in obtaining consistent and affordable electricity from the grid, leading them to invest in self-generation technologies. This paper examines the strategic decision of firms to self-generate electricity and the economic losses incurred during power outages. Using survey data from the World Bank Enterprise Survey (WBES) of 5639 manufacturing firms in ...
Aufsatz
Electron beam powder bed fusion of Ti-30Ta high-temperature shape memory alloy: microstructure and phase transformation behaviour
(2024-06-19)
The present study reports on additive manufacturing of a Ti-30Ta (at.%) high-temperature shape memory alloy (HT-SMA) using electron beam powder bed fusion (PBF-EB/M) technique. Detailed microstructure analysis was conducted to reveal the microstructural evolution along the entire process chain, i.e. from gas-atomised powder to post-processed material. PBF-EB/M processed structures with near full density and an isotropic, β-phase stabilised microstructure, i.e. equiaxed β-grains of around 20 μm in diameter with no ...
Aufsatz
Pulsed Propulsion of Unmanned Aerial Vehicles by Centrifugal Force Modulation - First-Order Theory and Practicability
(2024-05-16)
A novel technique suitable for the propulsion of small unmanned aerial vehicles (UAV) is discussed in this paper. This approach utilizes the rotational energy of airborne gyro rotors and converts it into translational propulsion for the vehicle. The energy conversion is achieved by generating precisely directed centrifugal force pulses through short-duration rotor unbalances. The accurate control of the timing and magnitude of these unbalances is crucial for successful propulsion generation. Our first-order theory ...
Aufsatz
FTIR spectroscopy and multivariate discriminant analysis for classifying bituminous mastics: Exploring aging states and mastic composition
(2024-07-02)
This study aimed to differentiate among various bituminous mastics through the analysis of FTIR spectroscopy data. The mastics, incorporating three filler types, a 50/70 penetration index binder, and foamed bitumen, underwent chemical examination via FTIR spectroscopy after exposure to various aging cycles. Employing different multivariate discriminant analysis approaches, the investigation identified an optimal method, i.e., PLSR-LDA, which achieved a prediction precision of 100 % in distinguishing between various ...
Aufsatz
Susceptibility of a Fe-Mn-Al-Ni-Cr shape memory alloy to environment-assisted corrosion cracking
(2024-06-20)
In recent years, iron-based shape memory alloys (SMAs) have become increasingly interesting for application in civil engineering structures. Promising candidates in the field are iron-based Fe-Mn-Al-Ni-X (X = Ti, Cr) SMAs. These alloys have demonstrated the potential to be used in various types of applications. While the fully recoverable martensitic phase transformation can be used for structures where high damping capacities are required, i.e. for high rise buildings in earthquake prone areas, it has been successfully ...
Aufsatz
Renewable energy as an alternative source for energy management in agriculture
(2023-07-03)
This study provides a high-level overview of alternative energy sources that can be harnessed to power agricultural operations, focusing on renewable energy technologies. When thinking about the overall economy around the globe, agriculture is vital. Energy is required at each step of production, from fertilizer production to fueling tractors for planting and harvesting. The high energy prices and unpredictable energy market significantly affect the input energy costs. Energy efficiency methods, when properly applied, ...