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Fuels & Lubes International Quarter Three 2015
braking and fuel economy as benefitting from higher
aluminium content.
The F-150 may be the first of many mainstream
consumer vehicles with significant aluminium alloy
content. According to a 2014 study based on a survey of
car and truck makers by Drucker Worldwide, the use
of sheet aluminium for vehicle bodies in North America
will grow 20-fold from 2012 to 2025, reaching a projected
1.8 billion kg. From 2012 to 2015, the average weight
increased by 20 kg. per vehicle, Drucker reported.
“Aluminium-bodied cars and trucks are coming in
a big way – and soon. Consumers won’t visibly notice
a different metal under the paint, but they’ll see
greater savings at the gas pump and experience better
performance and handling at the wheel,” said Tom
Boney, chairman of the Aluminum Transportation Group,
which commissioned the study. This trade group is part
of the Aluminum Association, which supports higher use
of aluminium in many applications.
In gearing up for F-Series sales that may top 700,000
vehicles this year, Ford made changes to its Dearborn
and Kansas City, Mo., U.S.A. truck plants. For instance,
the company invested in 500 new robots and installed
new press lines to stamp out different types of high-
strength, military-grade aluminium alloys, Levine said.
The company also created aluminium-capable body
shops to handle parts repair.
There have been reports that repairs to aluminium
body parts are more expensive and difficult than steel
parts. However, the new F-150’s modular structure
actually makes repairs easier, said Levine. Also,
aluminium alloy body parts are not more expensive,
he said. “Most exterior body panels have identical
replacement costs to the outgoing 2014 F-150 steel body
panels.”
In manufacturing those body parts, the typical starting
point is a sheet of metal, which is then formed by tooling
it into the correct shape. For example, the process
may involve pressing up the edges of the sheet while
forcing the middle down, with a lubricant making this
deformation easier. The strength of the material plays
a role, as does any surface coating. Other important
parameters are the viscosity and film thickness of the
lubricant, as well as the stability of these characteristics
under pressure and at certain temperatures.
Researchers at the Center for Precision Forming are
looking beyond lubricants to find the best recipe for
manufacturing high-strength materials. For instance,
rams are used to force the tooling into the metal.
Researchers are attempting to discover the optimum
speed that should be used.
They also are looking at completely different ways to
stamp metal parts. One option is warm forming. Unlike
cold stamping, manufacturers would heat up the sheet
metal to make it easier to form into the proper shape.
For instance, the metal may be worked at 200 degrees
Celsius (C) or higher, instead of at room temperature.
“In warm forming, of course we need lubricants that
can perform at the elevated temperatures used in this
process,” Altan said.
As part of its research, the centre is developing tests
to better evaluate lubricants. One involves cup-drawing
tests, which Altan said gave the best results in gauging
the lubricant’s effectiveness. This test begins with a
blank sheet of metal, into which a punch is pushed.
Lubricants are measured by how much deep drawing
force the holder can take before cup formation fails,
due to metal fracturing. Values reported so far show
that blank holder force can measure 30 or more metric
tonnes. These preliminary results indicate that it may be
possible to use this test to distinguish between various
lubricants.
Aluminium is only one of the new materials being
evaluated. Others include high-strength steel, alloys
of magnesium, fiber-reinforced plastic and carbon
fiber. Each presents its own opportunities for light
weighing. Each could also generate its own lubricant and
manufacturing challenges.
At the same time, it’s important to keep in mind that
the material serves the car and its buyer — not the other
way around. Thus, a manufacturer may have one vehicle
with high aluminium content, like the 2015 Ford F-150.
However, this does not mean that the rest of its products
will inevitably move towards a higher aluminium content.
“We treat each vehicle on a case-by-case basis, applying
the right material at the right time to improve efficiency
and performance,” said Levine.
In 1942, Freightliner’s first truck known as the Model 600 was
introduced in the market. It was the first commercial vehicle
with an all-aluminium cab. (Copyright Daimler. All Rights
Reserved.)
