| 1. |
- Akujärvi, Ville, et al.
(author)
-
Evolution of magnetic properties during tempering
- 2021
-
In: International Journal of Advanced Manufacturing Technology. - : Springer Science and Business Media LLC. - 0268-3768 .- 1433-3015.
-
Journal article (peer-reviewed)abstract
- Quality control in heat treatment of steel is often conducted after the treatment. Failure to confine within the specified range of mechanical properties may lead to wasted energy and production resources. Performing quality control in-line in the heat treatment process allows for early detection and possibility to react to changes in the process. The prospects of utilizing the change in the electromagnetic (EM) properties of steel, as means for quality control, are investigated in this paper. The focus is on the tempering process of hardened SS2244 (42CrMoS4) steel. The tempering takes the hardness of the steel from approximately 600 HV down to around 400 HV. The EM signature of the steel is recorded during the tempering process. This is later compared with results from more traditional means of material characterization, such as laser scanning microscopy, X-ray diffractometry and Vickers microhardness measurement. This initial study shows clear indications of precise detection of the hardness through EM properties during the tempering process of selected material.
|
|
| 2. |
- Akujärvi, Ville, et al.
(author)
-
Mapping of magnetic properties for simulations of high-Temperature electromagnetic applications
- 2017
-
In: COMPEL - The International Journal for Computation and Mathematics in Electrical and Electronic Engineering. - 0332-1649. ; 36:2, s. 546-554
-
Journal article (peer-reviewed)abstract
- Purpose -The purpose of this paper is to investigate the added value of using temperature-dependent electric and magnetic properties in high-Temperature electromagnetic simulations. Design/methodology/approach - In this work, the electromagnetic properties of Domex 420, SSAB, have been characterized as a function of the temperature, from room temperature to 900°C. The measurement of the electric and magnetic properties was performed inside a vacuum furnace at a number of discrete temperature steps, with particularly small intervals around the Curie temperature. A simple transient multi-physics model was used to investigate the impact of the measured properties in three different representations. Findings - In certain intervals, a simplified approximation of the properties produces accurate results, while fully parametric representation is beneficial when heating above the Curie temperature. Originality/value -Temperature-dependent electromagnetic properties are rarely found, especially in an easy-To-use form. Using parameterized temperature-dependent approximation of key properties shows noteworthy differences in the outcome of high-Temperature electromagnetic modeling.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Cedell, Tord, et al.
(author)
-
New advances in soft magnetic materials - properties of moulded flux conductors in inductors and electrical motors
- 2009
-
Conference paper (peer-reviewed)abstract
- A new technology has emerged the last decade, based on a new group of materials; Soft Magnetic Composites (SMC), instead of laminated steel that facilitates production of products with more integrated, smaller, lighter, less costly and highly efficient electromagnetic machines. The application of this technology is a change of paradigm regarding integrated design and energy efficiency. This article describes a new group of SMC’s; Soft Magnetic Mouldable Composites (SM2C). With this material it is possible to produce electromagnetic components, using rotational- or gravital moulding technology, RotoCast. This new production method allows for integration of parts, coils etc, but also has a potential for automated low cost and high rate production. It is possible to reach impressive magnetic, mechanic and thermal properties in rotation moulded parts. High performance inductors and electrical motors has been produced by RotoCast and evaluated. The maximum permeability of SM2C is in the order of 30. This is ideal for inductors, since the storage of reactive energy is distributed uniformly. The total production cost of this type of inductors can be very low compared to conventional ferrite/litz solutions. Since the high frequency magnetization losses are low and the thermal conduction is considerable, there will be no hot-spots. For motors, the low permeability gives lower torque compared to conventional laminated motor structures. This is compensated by increasing the radius of the motor, and since the high-frequency magnetization losses are low the number of poles can be made very high, thus reducing the magnetic material giving the motor high torque-to-weight ratio.
|
|
| 8. |
|
|
| 9. |
- Frogner, Kenneth, et al.
(author)
-
A method for fast characterization of power efficiency in induction heating processes
- 2012
-
In: ; , s. 303-309
-
Conference paper (peer-reviewed)abstract
- A method for fast and precise measurement of effciency in induction heating processes is evaluated and tested. The method, based on thermal imaging is presented with advantages and drawbacks based on results from coupled transient simulations and from experimental results. The experiments are performed using two different induction heating platforms, equipped with high quality measurement equipment, including a thermal camera, capable of streaming 16 bits radiometric data for image recording on a computer. Post-processing of the recorded data, including compensation of camera position and integration of electrical and thermal properties is explained and the results presented with pictures of each step. Also some basic knowledge of radiometric measurement of temperature is described to better understand the possibilities and to avoid unnecessary pitfalls. Guidelines of how to choose the best equipment or setup forms the conclusion of the article, providing a method that can be used also for other applications.
|
|
| 10. |
- Frogner, Kenneth, et al.
(author)
-
A new concept of coil design for industrial induction heating
- 2011
-
In: Proceedings of the Swedish Production Symposium 2011, SPS11.
-
Conference paper (peer-reviewed)abstract
- Abstract in UndeterminedThe demands for energy efficent heating solutions for the manufacturing industry can be met by a new induction heating platform, presented in this article. A new concept and technology to design and manufacture induction heating units is explained, evaluated and tested with successful results. The so called Greenheat technology relies on inductors built on Litz wiring moulded in soft magnetic composite; a flux conducting material produced using rotational casting methods. The aim of the article is to present and verify a hyphotesis of greatly improved induction heating results when modifying a traditional inductor design in four dependent steps. The verification is done using analytic solutions and FEM simulations as well as by experimetal work, clearly showing higher heating efficiency, no requirement for advanced cooling and a higher geometrical flexibility compared to existing heating solutions.
|
|
