| 1. |
- Van Den Berg, F. D., et al.
(författare)
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Product uniformity control - A research collaboration of european steel industries to non-destructive evaluation of microstructure and mechanical properties
- 2018
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Ingår i: Stud. Appl. Electromagn. Mech.. - : IOS Press. - 9781614998358 ; 43, s. 120-129
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Konferensbidrag (refereegranskat)abstract
- In steel manufacturing, the conventional method to determine the mechanical properties and microstructure is by offline, destructive (lab-)characterisation of sample material that is typically taken from the head or the tail of the coil. Since coils can be up to 7 km long, the samples are not always representative for the main coil body. Also, the time delay (typically a few days) between the actual production and the availability of the characterisation results implies that these results cannot be exploited for real-time adaptation of the process settings. Information about the microstructure and material properties can also be obtained from electromagnetic (EM) and ultrasonic (US) parameters, which can be measured in real-time, non-destructively, and over the full length of the steel strip product. With the aim to improve the consistency in product quality by use of inline EM and US measurements, a European project called "Product Uniformity Control" (PUC) has been set up as a broad collaboration between 4 major European Steel Manufacturers and 10 Universities / Research institutes. Using both numerical simulations and experimental characterisations, we study the inline measured EM and US parameters in regard of the microstructural and mechanical properties. In this way, we aim to establish an improved understanding of their mutual relationships, and to apply this knowledge in existing and new nondestructive evaluation techniques. In this paper, the concerted approach of modelling and experimental validation will be addressed, and results of this work will be shown in combination with inline measured data.
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| 2. |
- Wirdelius, Håkan, 1963, et al.
(författare)
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Validation of models for Laser Ultrasonic spectra as a function of the grain size in steel
- 2018
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Ingår i: 12th European Conference on Non-Destructive Testing (ECNDT 2018). - 9789163962172
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Konferensbidrag (refereegranskat)abstract
- To reduce costs of production and increase economic sustainability it is necessary to introduce quality assessment in an early stage in the manufacturing process. In an ongoing European project (Product Uniformity Control – PUC), the intention is to use ultrasonic information to assess microstructure parameters that are related to macroscale qualities such as mechanical properties. Laser induced ultrasonic technique (LUS) requires no media and can generate and detect ultrasonic information at some distance from the component. This technique is therefore addressed within this project as a solution to measure ultrasonic properties in an industrial environment. Mathematical modelling of the ultrasonic wave propagation problem has been used in order to get a deeper understanding of the physics and to identify ultrasonic properties that can be used as an indirect measurement of grain size. The use of both analytical and numerical models enabled extensive parametric studies together with investigation of ultrasonic interactions with well-defined individual microstructures. The LUS technique has previously been applied to e.g. monitor grain growth during thermomechanical processing of metals. These applications identified and used a correlation with the frequency content of the attenuation. This have been investigated as a possible indirect measurement of grain size, also in this project. The models have been used to verify the correlations and to evaluate different procedures that could be applied as an industrial solution. The suggested procedure is based on deconvolving two successive echoes and has been experimentally validated by two different LUS systems. The reference samples used in the validation were produced by changing the annealing temperature and time to obtain a variation in grain sizes. These grain sizes were then identified by EBSD and the samples were examined in terms of grain size influence on spectral attenuation
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| 3. |
- Gutiérrez, Lucía, et al.
(författare)
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Synthesis methods to prepare single- and multi-core iron oxide nanoparticles for biomedical applications
- 2015
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Ingår i: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 44:7, s. 2943-2952
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Tidskriftsartikel (refereegranskat)abstract
- We review current synthetic routes to magnetic iron oxide nanoparticles for biomedical applications. We classify the different approaches used depending on their ability to generate magnetic particles that are either single-core (containing only one magnetic core, i.e. a single domain nanocrystal) or multi-core (containing several magnetic cores, i.e. single domain nanocrystals). The synthesis of single-core magnetic nanoparticles requires the use of surfactants during the particle generation, and careful control of the particle coating to prevent aggregation. Special attention has to be paid to avoid the presence of any toxic reagents after the synthesis if biomedical applications are intended. Several approaches exist to obtain multi-core particles based on the coating of particle aggregates; nevertheless, the production of multi-core particles with good control of the number of magnetic cores per particle, and of the degree of polydispersity of the core sizes, is still a difficult task. The control of the structure of the particles is of great relevance for biomedical applications as it has a major influence on the magnetic properties of the materials.
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