Manufacturing Engineering

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Browsing Manufacturing Engineering by Author "Getasew Ashagrie (PhD)"

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    Effect Of Microwave Heat Treatment on Aluminum 6061 Alloy Alumina Composite
    (Addis Ababa University, 2025-06) Meron Workneh; Getasew Ashagrie (PhD)
    Aluminum matrix composites are becoming more prevalent in the automotive industry because of their advantageous properties relative to traditional materials such as Steel or even pure Aluminum, This is also applicable for automotive parts such as control arms, because they allow for lightweight designs with high strength and better stiffness. The present work utilizes stir casting technique for the fabrication and mechanical characterization of aluminum 6061 alloy with variable weight percentages (5%, 10% and 15%) of aluminum oxide (Al2O₃) reinforcement. The primary objective was to investigate the influence of microwave heat treatment on the mechanical properties of the composite. Mechanical tests such as hardness, tensile and flexural strength were carried out in accordance with ASTM standards to evaluate performance improvements. It was shown that as Al2O₃ increases in levels, all the attributes evaluated significantly improved. Stir casting combined with microwave treatment proved to be an effective processing route for the development of structural grade aluminum matrix composites. The composite with a composition of 15 % Al₂O₃ reinforced showed the promising results for double control arm application, with a tensile strength of 330 MPa, flexural strength of 411.3 MPa and Rockwell hardness of 74.3 HRB. These properties make the composite suitable for the intended application. Finite element analysis is carried out to validate the experimental findings using ANSYS 19.2 commercial software, demonstrate a strong correlation between experimental and ANSYS simulation the percentage error remains consistently low within 4% indicating reliability. For the application area analysis with a Von - Mises stress of 173.76 MPa and maximum total deformation of 0.135mm. The results obtained from both experiments and FEA show that the Aluminum 6061 matrix reinforced with Al₂O₃ composite is a suitable alternative for double control arm.
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    Multi-Criteria Decision-Making Methodology for Sustainability Performance Assessment of Plastic Cup Manufacturing: The Case of BA Manufacturing P.L.C.
    (Addis Ababa University, 2024-11) Abebaw Mengistu; Getasew Ashagrie (PhD); Ayalsew Dagnew (Mr.) Co-Advisor
    Since sustainability is a multidisciplinary concept, it requires strategic prioritization in today's world. Sustainable manufacturing aims to reduce adverse effects while enhancing the supply chain. However, many manufacturers continue to use substantial resources and produce waste and pollution during the process. Therefore, it is essential for manufacturers to seek operations that maximize economic viability and societal well-being while internalizing environmental externalities. Despite this, there is a lack of an effective multi-criteria decision-making methodology tailored to assess the sustainability performance of plastic cup manufacturing methods, considering the complex interdependencies between environmental, economic, and social dimensions. The purpose of this study is to apply the concept of sustainability to plastic cup manufacturing methods. By using a statistical frequency-counting method for indicator prioritization and carefully selecting indicator sets, the study employs the multi-criteria decision-making (MCDM) methodology of the Analytic Hierarchy Process (AHP) to assess the sustainability performance of these methods. The assessment examines the sustainability performance of different manufacturing methods and the contributions of various indicators based on the three sustainability pillars. A nine-point Saaty comparison scale is used for pairwise assessments, and the Borda count method is applied for overall sustainability evaluation. According to the analysis, vacuum forming has a higher overall sustainability performance score of 58.23%, compared to pressure forming, which scored 41.74%. The sustainability performance of each method was also examined, along with the contributions of each indicator. In the environmental dimension, pressure forming showed better performance with a score of 5.40%. In contrast, vacuum forming outperformed in the economic and social dimensions, with scores of 9.64% and 21.07%, respectively. This thesis demonstrates the effective application of a multi-criteria decision-making methodology to evaluate the sustainability performance of cup manufacturing methods. The research also proposes a framework that offers an accurate assessment and comparison of the sustainability performance of injection molding and thermoforming methods, with injection molding performing better.
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    Process Evaluation and Performance Enhancement of Corrugated Board Fabrication. (A case of Burayu Packaging and Printing Industry)
    (Addis Ababa University, 2023-07) Yohannes Eshete; Getasew Ashagrie (PhD)
    The materials utilized, the conversion process, and other factors could all have an impact on the corrugated board performance. The objective of the thesis to quantify the mechanical strength of the corrugated board, the adhesive strength, the paper compression strength at fabrication process of investigated the pin adhesive, edge crush, box compression strength and material properties test at standardize methods. Based on the experimental result the reel size of 165,185,205,220 cm at fabrication speed on 50,65,80,95 m/min which can be used to determine varies result of compression strength exhibited at 50 m/min, and the fabricated board was the maximum, pin adhesive 356,352,351,349 Newton, edge crush 4.5,4.3,4.2,4.4 KN/m, pure box compression 112- 114 kg strength were shown. Reel size 220 cm fabricated at 80 m/min refers to the laboratory results minimum strength were performed. The Maltenfort model by correlating the measured ring crush test with the theoretical edge compression test enable to know the board strength of how much the variables degraded the strength of the combined board as of reel size 185,205,220 cm at 80 and 95 m/min during the process. The regression equation which can be used to evaluate the linear effect of the process and can be used to predict the performance of the box and enable it to enter into optimum fabricating process as well as strength improvement decisions. Boards will have better strength if they follow optimum process can be achieved by balancing and selecting the variables of fabricating speed, reel size, and material properties which helps to identify the strength of the board and evaluate the fabrication process. Overall, this study provided experimental and McKee box prediction are done for the evidence of structural performance and delamination strength of the corrugated fiber board by aligning a process through runnability.