Manufacture of SiC Composite Parts Using Powder Metallurgical Methods Adrian Dunne, Dr. Lisa Looney and Dr. Jerry Murphy Materials Processing Research Centre, Dublin City University, Dublin 9, Ireland

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Manufacture of SiC Composite Parts Using Powder
Metallurgical Methods Adrian Dunne, Dr. Lisa
Looney and Dr. Jerry Murphy Materials Processing
Research Centre, Dublin City University, Dublin
9, Ireland
Some Parts Commonly made using Powder Metallurgy
Introduction To meet the very demanding
mechanical requirements of many of todays
material applications Metal Matrix Composites
(MMCs) have received more research attention in
recent times. Traditionally PM parts made of
Silicon Carbide (SiC) composite materials are
manufactured using an extremely expensive
processes. It has been shown that it is
possible to manufacture such parts using simple,
and cheap, uniaxial pressing. However the size
ratio of the powders has a big effect on the
final mechanical properties of the material. How
can we understand and model this phenomena?
Project Aims The main aim of this project is to
develop a model to describe the behaviour of the
SiC composite materials as processed by PM
methods with particular referance to the effects
of the relative sizes of the powders used.
Effect of different size combinations on Green
Density
Research A literature review of all papers in
the field of PM modelling has been carried out.
It has been seen that many different approaches
to such models exist and that the accuracy of
each depends on the circumstances in which they
are used. The models as constructed in this
research so far are in agreement with what is
seen experimentally i.e. that relative powder
size (RPS) has a large effect on the porosity of
the powder before compaction. This may well be
part of the reason for the dependence of
mechanical properties on RPS.
The Stages of Powder Metallurgy Manufacturing
PM PROCESSING ROUTE INVESTIGATED
Liquid Phase Sintering
Uniaxial Pressing
Mixing (Al SiC)