Browsing by Department "Materials to Products"

Now showing 1 - 8 of 8
  • No Thumbnail Available
    Item
    Additive manufacturing processes and materials for spare parts
    (Korean Society of Mechanical Engineers, 2023-11) Salmi, Mika; Pei, Eujin; Materials to Products; Brunel University London; Department of Mechanical Engineering
    Additive manufacturing (AM) has shown to have a high potential to produce spare parts on demand. However, the use of AM to produce spare parts on demand faces challenges related to material availability, quality, part size, cost, and pre- and post-processing operations. From existing literature, most studies focus on a single use case. Other studies focus on the applications of using AM from a general perspective, rather than a specific AM process. This study attempts to close this knowledge gap by considering the AM of spare parts and processes by undertaking a thorough review of scientific articles regarding different AM processes and materials being utilised for spare parts. Current publications do not explore all potential materials that are available, and do not investigate a broad range of industrial sectors. It was also found that the tooling industry and use for rapid prototyping are largely left out. The study also showed that the use of material jetting and binder jetting are less frequently used for end-use spare parts and sheet lamination is rarely used at all. In contrast, we found that directed energy deposition was most popularly used for repairing spare parts, followed by powder bed fusion and material extrusion that are prevalent in most industries. This study revealed that further development on the use of binder jetting and material extrusion would allow for more possibilities in the use of high-value pare parts for sectors such as aerospace, automotive, energy, defence, consumer products and medical industries.
  • Thumbnail Image
    Item
    Additively Manufactured 2D Matrix Code Direct Part-Marking Casting Requirements
    (American Foundry Society, 2023-10) Uyan, Tekin; Jalava, Kalle; Orkas, Juhani; Otto, Kevin; Materials to Products; Department of Mechanical Engineering; University of Melbourne; Department of Mechanical Engineering
    Direct part-markings (DPMs) can be formed into metal castings, using additively manufactured two-dimensional matrix encoded tags (AM2D) placed in a sand or shell mold. It has been unclear how thin a part can be and yet form a readable DPM. There must be sufficient molten metal to burn away the tag, and sufficient feeding pressure to form the 2D matrix code dot pattern. Here the formability limit for the casting of any AM2D (polymer) tag is shown to be the smallest heat energy from the latent heat of condensation needed to raise the temperature of the tag to ignition to burn the tag from the mold. The minimal part thickness that can be utilized is thereby derived. The minimum thickness is calculated to predict a part of various materials and compared positively with experiments. This provides a means to compute required part metal thickness to positively form a DPM tag before casting.
  • Thumbnail Image
    Item
    Defect detection in laser-based powder bed fusion process using machine learning classification methods
    (Institute of Physics Publishing, 2023-12-22) Akmal, Jan Sher; Macarie, Mihai; Björkstrand, Roy; Minet, Kevin; Salmi, Mika; Materials to Products; University of Twente; Department of Mechanical Engineering; Electro Optical Systems Finland Oy
    The aim of this study is to deploy machine learning (ML) classification methods to detect defective regions in additive manufacturing, colloquially known as 3D printing, particularly for the laser-based powder bed fusion process. A custom-designed test specimen composed of 316L was manufactured using EOS M 290 machine. Multinomial logistic regression (MLR), artificial neural network (ANN), and convolutional neural network (CNN) classification techniques were applied to train the ML models using optical tomography infrared images of each additively manufactured layer of test specimen. Based on the trained MLR, ANN, and CNN classifiers, the ML models predict whether the manufactured layer is standard or defective, yielding five classes. Defective layers were classified into two classes for lack of fusion and two classes for keyhole porosity. The supervised approach yielded impeccable accuracy (>99%) for all three classification methods, however CNN inherited the highest degree of performance with 100% accuracy for independent test dataset unfamiliar to the model for unbiased evaluation. The high performance and low cost of computing observed in this work can have the potential to detect and eliminate defective regions by tuning the processing parameters in real time resulting in significantly decreased costs, lead-time, and waste. The proposed quality control can enable mass adoption of additive manufacturing technologies in a vast number of industries for critical components that are design- and shape- agnostic.
  • No Thumbnail Available
    Item
    Densification, microstructural characterization, and the electrochemical behaviour of spark-plasma sintered Ti6Al4V-5Cr-TiB2 composites
    (The Korean Ceramic Society, 2023-05) Falodun, Oluwasegun Eso; Oke, Samuel Ranti; Akinwamide, Olukayode Samuel; Olubambi, Peter Apata; Covenant University; University of Johannesburg; Materials to Products; Department of Mechanical Engineering
    The impacts of Cr-TiB2 addition on densification, hardness, microstructure, phase transformation, and corrosion were examined. The results indicated an even and uniform dispersion of TiB2 particles in the titanium matrix, with no noticeable interfaces throughout the sintering process. The relative density of the sintered titanium-based composites dropped, with an increase in TiB2 percentage. The microhardness result indicated that Ti6Al4V has 326 HV0.5, while the maximum hardness was 598 HV0.5, produced from 20 wt.% TiB2 ceramic particles. The Ti6Al4V alloy depicts α-phase forms parallel plates in the prior β-grain borders and expands into the β-grain to create α-colonies, while the addition of 5–20 wt.% Cr-TiB2 resulted in a microstructural transformation characterized by equiaxed α-precipitates embedded within the β-phase matrix, for all samples. The electrochemical behaviour revealed that the Ecorr decreased as TiB2 increased, while the icorr was higher. However, samples containing 5Cr and 5Cr-5TiB2 moved to a more positive Ecorr region, whereas the icorr altered to a more negative area. This meant that the presence of ceramic reinforcements increased the corrosion resistance of the alloys and that higher concentrations of titanium diboride provided less protection against ion attack in a chloride environment.
  • Thumbnail Image
    Item
    Effects of ultrasonic burnishing on the surface quality of corrosion-resistant tool steel using a hard-carbon-coated burnishing tool
    (2023-04-19) Huuki, Juha; Ullah, Rizwan; Fangnon, Agbemon; Department of Mechanical Engineering; Materials to Products; Madej, Lukasz; Sitko, Mateusz; Perzynski, Konrad
    Ultrasonic burnishing is a relatively new and effective method for improving the surface finish of metal parts. Burnishing strongly affects the surface quality, improving surface properties such as, surface hardness and surface roughness. Previous studied have observed that changing some burnishing parameters significantly affects the burnished surface quality. In this research, using a carbon-coated burnishing tool, tangential misalignment angles were varied on a corrosion resistant tool steel that has not been previously investigated. Two different burnishing tools were used to study their effect on surface quality and surface hardness. The results revealed that coated tungsten carbide tool has produced superior surface finish compare to non-coated burnishing tool which is the new finding. It is rather surprising that surface roughness has not increased as it typically happens during burnishing but a clear surface roughness enhancement was observed. The results showed a clear improvement in surface roughness (80-86%), whereas surface hardness did not change significantly.
  • Thumbnail Image
    Item
    Efficient strategies for reliability analysis and uncertainty quantification for filament-wound cylinders under internal pressure
    (SAGE Publications, 2023-05) Azizian, Masoume; Almeida, Humberto; Azizian, Mohammad; University of Bonab; Materials to Products; Department of Mechanical Engineering
    Induced uncertainties during the filament winding process may cause a significant stochastic variation in the mechanical behaviour of composite shells. This paper aims to develop a novel and deep uncertainty quantification (UQ), sensitivity and reliability analyses of filament wound shells considering manufacturing uncertainties. Firstly, a progressive damage analysis is performed to estimate their deterministic burst pressure. Then, a signal-to-noise (SNR) approach is employed using the Taguchi method for sensitivity analysis and screening uncertainties arising from manufacturing. Initial results reveal that the shells are more sensitive to thickness uncertainties for thinner structures. Then, probabilistic and reliability analyses are carried out using the Boosted Decision Trees Regression (BDTR) approach from machine learning algorithms. Despite the complexity and non-linear relationships in the problem, the developed BDTR-based metamodel shows powerful predictive performance. A comparative study shows that ply thickness uncertainty leads to a significant underestimation of failure probability. For expensive and time-consuming models in that only a few runs can be affordable, a modified approximation method for reliability analysis is proposed. Results indicate a high capability at estimating failure probability with high accuracy.
  • Thumbnail Image
    Item
    Identifying and framing potential stakeholders in complex innovation ecosystems
    (CERN - European Organization for Nuclear Research, 2023-12-29) Eriksson, Vikki; Keipi, Teo; Björklund, Tua; Design Factory; Department of Mechanical Engineering; Materials to Products
    Analysing the types and connections to stakeholders may be daunting for engineering students. Creating stakeholder maps can be scaffolded through prompting for different stakeholder roles, which students may use as a starting point. Drawing from 31 student stakeholder analyses, this case study explores students’ ability to identify different types of stakeholders and the range of roles they could play, when provided with a set of stakeholder roles as a point of departure. Students were able to identify a diverse range of stakeholders as well as the multiplicity of stakeholder roles. The role prompting resulted in 36 unique stakeholders and 63 stakeholders identified by multiple students, particularly in customer, supplier, and possible collaborator roles. As such, combining individual, scaffolded mappings can help to capture innovation ecosystems more systematically and illuminate more diverse collaboration opportunities in development projects.
  • Thumbnail Image
    Item
    Prototyping in practice – Paths and partners for testing novel industrial product and service ideas
    (CERN - European Organization for Nuclear Research, 2023-12-29) Kirjavainen, Senni; Lahdenne, Simo; Björklund, Tua; Design Factory; School common, SCI; Materials to Products; Department of Mechanical Engineering
    Prototyping is a core activity when developing new products, processes, and organisations alike. This paper describes the prototyping activities of 31 engineering design professionals in a high-technology industrial company. Findings examine the distribution of different types of activities across different phases of development based on thematic interviews. Examining 62 prototyping and testing pathways, we found that most prototyping paths started with the practitioners’ own activities. These pathways were more likely to lead to prototyping paths with increased prototyping steps, than if the first prototyping activity took place in collaboration with a stakeholder. Overall, the pathways were short, which may indicate a lack of iteration. Both internal and external stakeholders were involved in collaborative prototyping, which was enabled by personal and unit level relationships. It was noted that different stakeholders were involved in different phases of development. Taken together, our results suggest thatpractitioner attention in prototyping may focus on latter development phases and demonstrate less iteration than what literature might suggest. In addition, findings highlight that opportunities for prototyping often depend on personal networks in the high-technology context if flexible prototyping budgets are not possible. We suggest organizations pay attention to supporting collaboration and prototyping throughout development processes.