Development of a Low-Expansion and Low-Shrinkage Thermoset Injection Moulding Compound Tailored to Laminated Electrical Sheets-Reference-Cited by-同舟云学术

Development of a Low-Expansion and Low-Shrinkage Thermoset Injection Moulding Compound Tailored to Laminated Electrical Sheets

Published:2024-07-18 Issue:7 Volume:15 Page:319
ISSN:2032-6653
Container-title:World Electric Vehicle Journal
language:en
Short-container-title:WEVJ

Author:

Braunbeck Florian¹^ORCID,Schönl Florian²^ORCID,Preußler Timo³^ORCID,Reuss Hans-Christian⁴,Demleitner Martin²,Ruckdäschel Holger²^ORCID,Berendes Philipp³

Affiliation:

1. Porsche AG, 70435 Stuttgart, Germany

2. Department of Polymer Engineering, University of Bayreuth, 95447 Bayreuth, Germany

3. Department of Lightweight Design, Institute for Engineering Design and Industrial Design, University of Stuttgart, 70569 Stuttgart, Germany

4. Department of Automotive Mechatronics, Institute of Automotive Engineering, University of Stuttgart, 70569 Stuttgart, Germany

Abstract

This study presents a thermoset moulding compound designed for electrical machines with high power densities. The compound reduces residual stresses induced by the difference in thermal expansion during use and by shrinkage in the compound during the manufacturing process. To reduce the internal stresses in the compound, in the electrical sheet lamination and at their interface, first the moulding’s coefficient of thermal expansion (CTE) must match that of the lamination because the CTE of the electrical sheets cannot be altered. Second, the shrinkage of the compound needs to be minimized because the moulding compound is injected around a prefabricated electrical sheet lamination. This provides greater freedom in the design of an electric motor or generator, especially if the thermoset needs to be directly bonded to the electrical sheet. The basic suitability of the material for the injection moulding process was iteratively optimised and confirmed by spiral flow tests. Due to the reduction of the residual stresses, the compound enables efficient cooling solutions for electrical machines with high power densities. This innovative compound can have a significant impact on electric propulsion systems across industries that use laminated electrical sheets.

Publisher

MDPI AG

Link

https://www.mdpi.com/2032-6653/15/7/319/pdf

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