Aluminum in US coins
By Daniel Borodin, Mustaffa Jaffar, et al.
Sustainability-Team Definition
• Sustainability is a method of economic use of Earth’s resources
by creating more efficient systems, through technological
advancement
• It is a way to ensure that humans live in harmony with nature
and that future generations will have access to important
resources for survival
Rationale for Change
• Our team was looking for something that was both very common
and useful if made more sustainable
• Our goal was to choose a product which could easily and effectively
be changed without causing further waste of resources
• We want to make changes on a bigger scale, not only at University,
to help economy and the environment
Original Design-Comparison
• The coin design and the
method of producing a master
hub from which the coins could
be duplicated will be the same
• However, aluminumcontaining coins could help
save money because of the
usefulness of certain
properties of the metal
New coinage
• In the new design we will attempt to change the composition of
Dimes, Quarters, and Nickels
• Dimes and Quarter, which consist of 8.333% nickel and rest copper,
will be changed to containing 2.5% Cu, same Ni, and rest Al
• Due to uncertainty in the alloy’s properties, the % of Al might have
to be lowered
• Nickels, with 25% Ni and rest Copper will be changed to having
2.5% Cu, same Ni, and rest Al
Advantages of Aluminum
• Aluminum is one of the most malleable metals and has lower
melting point: it’s an advantage because making coins requires
heating the alloy to make stamping possible, so with Al less heat can
be used
• Alloys are known to be harder that pure metals, so Al-Cu-Ni alloy
would also not wear out because of its resistance to corrosion
• Aluminum is the most conductive metal per weight, which could
make coins easily detected by vending machines, examined for
fakeness, and counted with lasers
• Since Aluminum is lighter than Copper, the main component of US
coins, using Aluminum could reduce transportation and handling
costs and would be easier to handle by regular people
• Aesthetic look to Al alloys would make good-looking coins
• Since heating tarnishes the coins in normal production, they must
be fed to a tank filled with chemicals that would restore its shine
• Al alloys, with their luster, could make away with the tank and
reduce spending even further
Cost estimate―Old design vs. New
• As previously shown, less energy could be used overall:
electricity, chemicals, fuel
• When coins are punched, the remaining scrap will be easier to
recycle, adding to overall efficiency and sustainability
• The new coin manufacturing may rely on fewer machines due
to properties of Al metal
Saving Calculations
Type
# made in
2012
Old per coin
cost
New per coin
cost*
Total savings per
year assuming
same #
Quarter
568,010,000
11.14 cents
8.367 cents
15.75 m$
Nickel
1,023,600,000
11.18 cents
9.179 cents
20.48 m$
Dime
1,676,000,000
5.65 cents
4.515 cents
19.02 m$
TOTAL
* Production cost assumed to be the same
~55.25 m$
Implementation
• Our team’s future research on the specific alloy and the method of
preparing it could be submitted to the US bursary
• Make a prototype coin and measure energy costs and savings
• Test the coin for physical properties such as impact absorption, tensile
strength, reduction in area, conductivity, specific heat, etc.
• Spread news about possible savings and make a report with all the
steps thoroughly explained and comparisons stated
• Make a survey/ surveys to see how many people support the idea of
changing the metal in coins to aluminum
Simple block diagram
Creation
of Alloy
Arranging
and
transporting
Craps are
collected
Forming alloy
into Metal
Sheets
Stamping
coins, easier
than before
Washing,
drying, and
upsetting, also
easier
Heating coins,
easier than
before
Lower boiling point of
aluminum allows easier
fractional distillation
Purification
of aluminum
and reuse