EPSRC/GKN Studentship in Soft Composite Magnetic Materials
Lead Research Organisation:
University of Cambridge
Department Name: Engineering
Abstract
Electrical motors are at the heart of modern society and with the growing importance of electric vehicles, and in the medium to long term electric aircraft, their importance will grow. The ability to make compact and powerful motors with high efficiency is thus a key enabling technology.
All motors contain soft magnetic materials that act to transmit magnetic flux. These materials generate losses in two ways, firstly through the hysteresis loop and secondly through eddy current losses. An ideal soft magnetic material thus combines high resistance, high saturation magnetisation with a low coercive field. It is difficult to find a single material that optimise all these properties and consequently most modern motors use laminated cores. The laminations serve to reduce eddy currents and the motor is designed so as to ensure so far as possible that the laminations cut across any likely current loops.
The anisotropic nature of laminated cores is a constraint on the motor designer which would ideally be removed. One way of achieving this is to use magnetic materials made from particles of a soft magnetic material that are bonded together by an insulating layer. The small size of the insulated particles limits the eddy current losses. The performance of these materials is currently limited by the non-magnetic insulating layer in the material which allows flux generated by individual particles to close.
The student working on this project will work closely with a leading manufacturer of soft magnetic composite powder GKN Sinter Metals, and their US subsidiary Hoeganaes Corporation, in order to gain a comprehensive understanding of how the physical and magnetic properties of the final pressed composite relates to the initial powder and the processing conditions. The successful applicant will develop a model of the compaction process that can then be used to develop improved process and materials. The project will involve the use of a wide range of experimental tools including SEM, X-Ray CT, SQUID magnetometry, mechanical testing in addition to materials modelling. The understanding gained will be used to develop improved materials and processing techniques, and thereby improved lightweight motors for a wide range of applications ranging from pancake motors for electric bikes to high speed and high power motors for aerospace.
All motors contain soft magnetic materials that act to transmit magnetic flux. These materials generate losses in two ways, firstly through the hysteresis loop and secondly through eddy current losses. An ideal soft magnetic material thus combines high resistance, high saturation magnetisation with a low coercive field. It is difficult to find a single material that optimise all these properties and consequently most modern motors use laminated cores. The laminations serve to reduce eddy currents and the motor is designed so as to ensure so far as possible that the laminations cut across any likely current loops.
The anisotropic nature of laminated cores is a constraint on the motor designer which would ideally be removed. One way of achieving this is to use magnetic materials made from particles of a soft magnetic material that are bonded together by an insulating layer. The small size of the insulated particles limits the eddy current losses. The performance of these materials is currently limited by the non-magnetic insulating layer in the material which allows flux generated by individual particles to close.
The student working on this project will work closely with a leading manufacturer of soft magnetic composite powder GKN Sinter Metals, and their US subsidiary Hoeganaes Corporation, in order to gain a comprehensive understanding of how the physical and magnetic properties of the final pressed composite relates to the initial powder and the processing conditions. The successful applicant will develop a model of the compaction process that can then be used to develop improved process and materials. The project will involve the use of a wide range of experimental tools including SEM, X-Ray CT, SQUID magnetometry, mechanical testing in addition to materials modelling. The understanding gained will be used to develop improved materials and processing techniques, and thereby improved lightweight motors for a wide range of applications ranging from pancake motors for electric bikes to high speed and high power motors for aerospace.
People |
ORCID iD |
| John Durrell (Primary Supervisor) | |
| Benjamin Dyer (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509620/1 | 01/10/2016 | 30/09/2022 | |||
| 1876703 | Studentship | EP/N509620/1 | 01/10/2017 | 30/09/2021 | Benjamin Dyer |
| Description | Multiple new coating materials have been developed with improved performance versus current industry products. These coating materials can be broadly split into two separate categories; liquid glass based coatings and silane based coatings. |
| Exploitation Route | These new coating materials are being taken forward by the industrial sponsors. Samples have been sent to two divisions of the industrial sponsors for validation of results. Results from the industrial sponsors have been positive. Industrial sponsors are keen to scale up this research to use for commercial purposes. |
| Sectors | Aerospace, Defence and Marine,Electronics,Energy,Manufacturing, including Industrial Biotechology,Transport |