Faculty of Mechanical Engineering

Permanent URI for this communityhttps://repository.ukim.mk/handle/20.500.12188/13

Browse

Settings

Author: search.filters.author.Aleksandra KrstevskaLanguage: search.filters.language.English

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Sustainability and environmental life cycle analysis of welding processes
    (International Journal of Structural Integrity, Emerald Publishing Limited, 2024-07-29)
    Elisaveta Doncheva
    ;
    Nikola Avramov
    ;
    Aleksandra Krstevska
    ;
    Martin Petreski
    ;
    Jelena Djokikj
    Purpose–Welding is a widely used manufacturing process in many industries. The process consumes a lot of energy and resources, pollutes the environment, and emits gases and fumes into the atmosphere that are dangerous to human health. There are various welding processes, and the suitable welding process is usually chosen based on cost, material, and conditions. Subjectivity is the most significant impediment to selecting an optimal process. As a result, it is critical to develop the appropriate set of criteria, use the best tool and methodology, and collect sufficient data. This study examines the sustainability of welding processes and their environmental impact. Design/methodology/approach– The welding process’s sustainability was examined and discussed in general, considering the technological specifics of each welding process, physical performance, and environmental, economic, and social effects. The study investigates the environmental impact of MMAW, GMAW, and GTAW/GMAW processes through experimental work and LCA methodology. Findings– MMAW is the most environmentally harmful technology, whereas GMAW has the least impact. The GTAW/GMAW process outperformed the other processes in terms of yield stress, but the analyses revealed that it had a greater environmental impact than GMAW. Originality/value– The study provides an environmental impact summary and demonstrates the effects of welding parameters and processes. This gives users an understanding of choosing the best welding technique or making the process more environmentally friendly. These recommendations help policymakers identify hot spots and implement the right plans to achieve more sustainable manufacturing.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Wire-arc additive manufacturing: recent developments and potential
    (The Academy of Applied Technical Studies Belgrade, 2023-12)
    Elisaveta Doncheva
    ;
    Aleksandra Krstevska
    ;
    Marjan Djidrov
    ;
    Filip Zdraveski
    ;
    Trajche Velkovski
    Wire-arc additive manufacturing (WAAM) is a promising technology for producing medium and large components without traditional subtracting technologies. It is a hybrid of two manufacturing techniques: additive manufacturing and welding. The use of this technology has grown significantly due to advantages such as material and energy savings while achieving high deposition rates and low cost. However, there are some issues with microstructure homogeneity, and properties are affected due to the complexity of the arc-induced thermal cycles and metallurgical mechanisms, resulting in high residual stresses, distortion, porosity, cracks, and delamination. This article summarises the progress made in the field of wire additive manufacturing, with a focus on welding systems, tool path design software, material analysis, and control systems. It also highlights some critical aspects that must be addressed to ensure high-quality production, such as control and diagnosis mechanisms for defect monitoring, the effects of parameters and their optimisation possibilities for improving quality, ensuring process stability, and possible post-deposition heat treatments. The conclusions suggest further improvements to the wire-additive manufacturing process in terms of accuracy, reliability, and efficacy, as well as future applications of the technology and research activities.