Thesis-2013-Swarbrick.pdf (8.27 MB)
Understanding the impact of coatings on the friction performance of carbon fibre ceramic composite brakes
thesis
posted on 2014-06-27, 08:05 authored by Arthur L. SwarbrickIn the railway industry, and premium luxury and super sports sectors of the automotive industry,
traditional cast iron brake discs are gradually being replaced with advanced composites such as carbon
fibre reinforced carbon silicon carbide (Cf/C-SiC). These materials offer the ability to operate at higher
temperatures, whilst displaying improved friction performance, and vastly reduced wear rates. Their
primary benefit comes from being approximately one third of the density of the incumbent material used
in the industry, grey cast iron (GCI), a cast iron with a high proportion of graphite flakes formed during
solidification. This reduced density means that brake discs manufactured from Cf/C-SiC materials are a
highly suitable proposition for a future automotive market, where weight saving in an attempt to meet
ever restrictive CO2 emissions is a must.
The understanding surrounding the friction mechanisms involved with these new materials has been
lacking, until recently, with the majority of the international research focused on the manufacturing
methods. Research has shown that friction performance, particularly bedding friction, is highly dependent
on the successful formation of a friction transfer film (FTF) at the surface of any disc, comprised from
wear debris from both the disc and pad. Prior research carried out at Loughborough University has
identified that Cf/C-SiC materials do not readily form such a layer, as might be seen on a GCI equivalent,
due to the intrinsically heterogeneous nature of the composite material. [Continues.]
Funding
TSB
History
School
- Aeronautical, Automotive, Chemical and Materials Engineering
Department
- Materials
Publisher
© Arthur SwarbrickPublication date
2013Notes
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.Language
- en