FAQs
WHAT IS MAGNESIUM?
Magnesium – atomic symbol Mg and atomic number
12 – is one of the most abundant elements in
the earth’s crust. It occurs in nature principally
as the minerals magnesite [MgCO3] and dolomite [(MgCaCO3]
and in seawater where it is the third most plentiful
component.
In its metallic form, magnesium metal has a number
of significant properties that are invaluable in our
advanced, technology driven environment. It is lightweight,
less than two thirds the weight of aluminium, with
a high strength-to-weight ratio. It
also has high damping and rigidity properties and as
such is finding increasing uses as a structural component
in a number of industries, especially the automobile,
aerospace and consumer product industries.
Magnesium metal can be machined faster and requires
less energy than any of the commonly used structural
metals such as steel and aluminium. This results in
significant improvements in tool life and hence savings.
Magnesium alloys are relatively light – about
33% lighter than aluminium alloys and about 75% lighter
than cast iron. In the automotive sector, magnesium
alloys (generally magnesium alloyed with aluminium
and either zinc or manganese) are used to make die
cast components such as steering wheels, suspension
components, seat frames and brake parts.
WHAT ARE THE
MAJOR APPLICATIONS OF MAGNESIUM?
Magnesium has a wide number of applications, both
as the metal as well as a range of compounds, especially
based on the oxide, MgO. Magnesium oxide is a major
component of a wide range of ceramic and refractory
materials used in domestic and industrial applications,
and an important ingredient in various consumer products
for the agricultural, horticultural and pharmaceutical
sectors. Magnesium is an essential element for all
living organisms, both animal and plant.
The traditional uses of magnesium metal fall into
the following major categories:
- as an additive to a wide range of aluminium alloys
in pure magnesium form,
- as an alloy of magnesium for
die-casting, granules or wrought products (extrusion
sheet plate),
- as a chemical reductant for the production
of other high-value metals, especially titanium,
and as a catalyst or reagent in the industrial chemicals
industry, and/or
- as a means of purifying crude iron
and steel products.
In some applications magnesium metal is used as such,
but most applications involve the use of an alloy of
magnesium. zinc, strontium, manganese, aluminium, beryllium
and rare earth metals are the common alloying metals.
In the past the quality of the magnesium metal and/or
alloy used in many of the above applications was not
critical. However, most of the modern industrial applications
of magnesium require a much higher grade of magnesium
metal and/or alloy in order to impart the required
physical and chemical properties, such as structural
strength, corrosion and resistance.
These higher quality magnesium alloy products are
available in a variety of forms including castings
(die, sand, permanent mould and investment), extrusions,
forgings and rolled products. Magnesium metal and its
alloys can be joined by traditional welding and riveting
techniques. As such, these products are finding increasing
applications where the combined strength and corrosion
resistance attributes allow for enhanced energy savings.
For example, in the US there are legislated regulations
that require the fuel consumption of the standard family
car to be substantially reduced over the next two decades.
One way of achieving this is to lower the overall weight
of the vehicle via the use of a higher percentage of
light-weight magnesium alloys. Not only does this save
energy, but it also reduces greenhouse gas emissions.
Within the next 8-10 years the amount of magnesium
used in the automotive industry is expected to increase
by at least 300%.
Modern life abounds with a variety of portable electronic
and other consumer goods and here again the use of
magnesium and its alloys is increasing.
Selected examples of the expanding applications of
magnesium and its alloys include the following:
Aerospace Industry
Brake devices, gear boxes, helicopter transmission
casings, turbine engines and wheels.
Automotive industry
Over 100 difference components, console brackets, engine
blocks, gear boxes, seat supports, steering column
assemblies, locks and brackets, support beams, transfer
cases, transmission housings, valve covers and wheels.
Consumer Goods
Bicycle frames, camcorders, digital cameras, in-line
skates, laptops, mobile (cell) phone and satellite
phones, ski bindings, tennis racquets and TV cabinets.
The major companies involved in the aerospace and
automotive industries, including Boeing, Airbus, Ford,
General Motors, Volvo, VW and Toyota, all have a significant
technical and commercial involvement in the development
and application of high performance magnesium alloys
in their industries.
HOW ARE MAGNESIUM METAL AND MAGNESIUM
ALLOYS PRODUCED?
There are two basic methods for producing magnesium
metal. The first involves the high temperature reduction
of a suitable source of magnesium such as magnesite
or dolomite, the other involves the electrochemical
reduction of magnesium chloride. The magnesium chloride
can be derived from sea water or other magnesium-containing
brines or via the chemical processing of magnesite
or dolomite. The high temperature reduction process
is generally carried out on a batch basis, whereas
the electrochemical route is carried out on a continuous
basis.
Magnesium alloys are prepared by melting together
the required amounts of alloying components with magnesium
metal produced by one of the two production methods
noted above. The molten alloys are subjected to appropriate
refining techniques before being cast into ingots,
the size and shape of which are matched to the requirements
of the customer, such as a die caster producing components
for the automotive industry.
In the past alloying and refining has been carried
out via a so-called crucible-to-crucible technique.
This is not particularly efficient, leading to relatively
high metal losses and the generation of excessive quantities
of product that does not meet the specifications for
the high performance alloys, as demanded by most end
users, especially those in the aerospace and automotive
industries. The salt refining technology used by Quay
Magnesium, on the other hand, yields products of the
required specifications and is more energy efficient
and has substantially lower metal losses.
WHAT IS THE
CURRENT AND FUTURE DEMAND FOR MAGNESIUM AND MAGNESIUM
ALLOYS?
Current world consumption of magnesium metal and magnesium
alloys is in excess of 750,000 tonne per annum. Market
projections indicate that consumption will increase
rapidly to over 500,000 tonne per annum.
Of the various applications of magnesium and its alloys,
die casting is the fastest growing sector of magnesium
consumption. For example, die casting applications
specific for the automotive industry are expected to
increase by about 8 – 10% per annum over the
next decade. 2008 estimates are 250,000 metric tonnes.
WHO
ARE MAGNESIUM/MAGNESIUM ALLOYS PRODUCERS?
China is the largest producer and exporter of primary
magnesium in the world today. The Chinese dominance
of the industry is a reflection of its abundant primary
sources of magnesium (magnesite and dolomite) and its
relatively low-cost labour and energy. Currently there
are around ninety (90) primary producers of magnesium
in China, with all facilities using the high temperature
reduction process commonly known as the Pidgeon process.
Other major producers include Dead Sea Magnesium,
US Magnesium and a number of operations within the
Russian Federation.
Quay Magnesium uses advanced salt refining technology
to produce magnesium alloys of the highest quality that
are expected to comply with, or exceed the current and
anticipated future specifications for all of the high
performance applications of magnesium alloys.
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