Co-operative Research projects for SMEs - European Commission ...

Magnesium on wheels
“The project includes the best people
Over the last decade or so, many manufac-
from lubricant producers to tool makers
turers, in particular the automotive industry, have
and the end-user.”
moved to reduce energy and costs by replacing traditional
materials like steel with lighter plastics and metals. Magnesium and
magnesium-based hybrid materials are becoming increasingly popular as they
combine high strength with low density. However, machining these materials presents
major challenges in terms of quality and safety. Ecohyb brings together partners from along
the machine tool supply chain to investigate best practice and improve methodologies for machining
magnesium materials. The Co-operative Research project will benefit all stakeholders through better quality
products and will open up new business opportunities.
In heavy manufacturing, efforts to save energy costs for industry and
produce energy-efficient products for customers have led to the introduction
of components made from lighter materials. In the automotive
industry, the weight of a typical mid-range car has been considerably
reduced by replacement of steel with aluminium and
plastics. Today, magnesium and magnesium hybrid materials are
attracting greater interest. These magnesium-based materials have
a 33% lower density in comparison to aluminium and 77% compared
to steel. Magnesium can also be formed into complex part
shapes, while the hybrid materials have low weight combined
with good strength and wear properties.
It is clear that vehicle and other manufacturers are looking to
increase their use of magnesium-based materials in the coming years,
in particular in larger auto parts that are moved around the assembly
area. The favoured types of material include magnesiumaluminum
(Mg-AI) hybrids and magnesium sintered metal hybrid
constructions.
However, there are a number of issues relating to the safe and accurate
machining of magnesium hybrid materials that must be resolved
if the European metal machining industry is to be able to respond
effectively to this market ‘pull’ and provide the services its customers
demand.
A magnesium machine
Machining hybrid aluminium/magnesium components presents a
number of difficulties. The two metals have different machining qualities
and the machine tool parameters need to be adjusted when
moving from one to the other to avoid quality discontinuity.
Magnesium also has issues relating to fire and explosive safety during
machining. This can either arise from the chipping or cuttings
from the magnesium material itself or as a consequence of the chemical
reaction of magnesium (abstraction of hydrogen) with the
large amounts of cooling lubricant used.
The Ecohyb consortium will develop a machine tool prototype that
is capable of the safe machining of magnesium-based hybrid materials.
In parallel, the project will optimise tools, machining strategies
and develop appropriate cutting lubricants. Standards for minimumquantity
machining of magnesium-hybrid materials will also be set.
To achieve this, Ecohyb has assembled a project team possessing
skills from a wide spectrum of the machine tool value chain. The
Co-operative Research project is being coordinated by Profactor
Produktionforschungs GmbH of Austria – an industrial research
organisation. Other project members include a machine tool maker
(Anger Anton in Austria), a cutting-tool manufacturer (Losconczi
Mernoki, Hungary), a machine-tool lubricant producer (Brugarolas
of Spain), two further research organisations (Budapesti Muszaki
of Hungary and Fundación Tekniker of Spain) and a machine tool
end-user (Protan Productionstechnik).
Hot chips need special care
The specially designed machine tool must have inherent safety concepts,
and specific lubricants are required to machine hybrid magnesium
materials safely. In particular, sintered metal/magnesium
hybrids will produce high-temperature sintered metal chips and highly
flammable magnesium chips. The different cutting forces experienced
by the tool as it moves between the different materials in
a hybrid call in part for detailed investigations of the behaviour of
the cutting tools, their cutting edges and various coating materials.
In addition, the production of very stable machine tools is a
prerequisite for the successful working of hybrid materials.
To avoid dangers of ignition, current technologies for machining magnesium
use large amounts of cooling lubricants
– oil or emulsions – that
flush the hot chips from
the working area.
This results in
additional hazards
such as
the possible
A magnesium
engine casing with
hybrid ‘half shells’ –
two materials requiring
one machining operation.
ECOHYB