Bronze - (Cu+Sn)
Melting
Point:
1562-832
Fahrenheit
\ 850-1000
Celsius
Boiling
Point:
Fahrenheit
\ Celsius
Bronze is
a metal
alloy
consisting
primarily
of copper,
usually
with tin
as the
main
additive
but comes
in many
alloy
configurations
each with
different
properties.
This
moderate
yellowish
to olive
brown
metal
alloy is
hard and
brittle,
but is
considerably
less
brittle
than iron.
Bronze is
generally
harder
than
wrought
iron, with
Vickers
hardness
of 60–258
vs. 30–80
and is
nonmagnetic.
Bronze
resists
corrosion
(especially
seawater
corrosion)
and metal
fatigue
more than
steel and
is a
better
conductor
of heat
and
electricity
than most
steels.
Typically
bronze
only
oxidizes
superficially
once a
copper
oxide
(eventually
becoming
copper
carbonate)
layer is
formed,
the
underlying
metal is
protected
from
further
corrosion
However,
if copper
chlorides
are
formed, a
corrosion-mode
called
"bronze
disease"
will
eventually
completely
destroy
it.
Bronze has
very low
metal-on-metal
friction.
Unlike
steel,
bronze
struck
against a
hard
surface
will not
generate
sparks, so
it (along
with
beryllium
copper) is
used to
make
hammers,
mallets,
wrenches
and other
durable
tools to
be used in
explosive
atmospheres
or in the
presence
of
flammable
vapors.
The alloys
of copper
and tin
and were
the first
to be
developed
about four
thousand
years ago.
There are
many
different
bronze
alloys but
modern
bronze is
typically
88% copper
and 12%
tin while
Commercial
bronze
(90%
copper and
10% zinc).
Architectural
bronze
(57%
Copper, 3%
Lead, 40%
Zinc) are
more
properly
regarded
as brass
alloys
because
they
contain
zinc as
the main
alloying
ingredient.
They are
commonly
used in
architectural
applications.
Bismuth
bronze is
a bronze
alloy with
a
composition
of 52%
copper,
30%
nickel,
12% zinc,
5% lead,
1%
bismuth.
It is able
to hold a
good
polish and
so is
sometimes
used in
light
reflectors
and
mirrors.
The
addition
of small
amounts
(0.01-0.45)
of
phosphorus
further
increases
the
hardness,
fatigue
resistance
and wear
resistance
leading to
applications
such as
springs,
fasteners,
masonry
fixings,
shafts,
valve
spindles,
gears and
bearings.
Cast
phosphor
bronzes
with up to
10% tin
and 20%
lead are
widely
used for
heavy duty
bearings.
Aluminum
Bronze
These are
alloys of
copper
with 5 -
12%
aluminum,
some
having
additions
of iron,
nickel,
manganese
and
silicon,
available
in cast
and
wrought
form. They
are
stronger
than the
brasses or
tin
bronzes
with
better
corrosion
resistance
due to a
hard,
adherent,
protective
alumina
film
(Al2O3)
They have
an
attractive
golden
color,
with very
little
tarnishing
with time.
The major
use for
aluminum
bronzes is
in sea
water
applications,
such as:
Fasteners
Pumps and
valve
components
Pipe
fittings
Heat
exchangers
Bearings
Silicon
Bronze
These are
alloys of
copper
with 3%
silicon
and 1%
manganese.
Silicon
bronzes
have a
good
combination
of
strength
and
ductility,
good
corrosion
resistance
and easy
weldability.
They are
used in
architectural
applications
such as:
Door
fittings
Railings
Church
doors
Window
frames
Hinges
Wall ties
Fastener
material
for marine
applications,
The alloy
is a firm
favourite
with
sculptors
and
metalsmiths
because of
its
workability,
longevity
and
attractive
golden
bronze
color.
Manganese
Bronze and
Architectural
Bronze
There may
be
confusion
when
brasses
are
incorrectly
called
bronze.
Manganese
bronze
CuZn40Mn1Pb1
(CW720R)
is a brass
used for
architectural
applications
where the
manganese
leads to
the
formation
of an
attractive
chocolate
brown
color. The
term
'architectural
bronze' is
sometimes
applied to
a leaded
brass
CuZn41Pb1Al
which in
service,
due to the
aluminum,
develops
an
attractive
golden
luster.
Like all
brasses
these
alloys
combine
longevity
with an
aesthetic
appeal
which
improves
with time
and they
give a
feeling of
luxury and
prestige
both
inside and
out to any
building.
They are
available
in all
forms and
are used
for
cladding,
windows,
doors and
curtain
walls.
They are
usually
finished
by waxing.
Bronze
Alloys
Bronze
(copper
and tin)
alloy is
generally
ductile
and
malleable.
Its high
copper
content
makes it
more
corrosion
resistant
than
brass. It
is also
harder and
stronger
than
copper.
Alloys
types are
220 -
Corrosion
Resistant
316 -
Machinable
and
Corrosion
Resistant
510 -
Ultra
Strength
544 - High
Strength
Bearing
Grade
630 - High
Strength
642 -
Machinable
High
Strength
655 -
Weldable
High
Strength
863 -
Corrosion
Resistant
High
Strength
903 -
Weldable
Bearing
Grade
932 -
Bearing
Grade
936 -
Machinable
Bearing
Grade
954 -
Corrosion
Resistant
Bearing
Grade
SAE 64 -
Machinable
Bearing
Grade
SAE 660 -
Bearing
Grade
SAE 841 -
Oil-Filled
Bearing
GradeSilicon
Bronze
About
Metal Spot
Prices:
The spot
price of
metals is
based on
paper
contracts
for
delivery
of tons of
pure metal
ingots.
When
you're not
prepared
to pay for
and take
delivery
of tons of
metal
ingots,
that spot
price will
quickly
become a
huge
understatement
of the
real price
of that
metal.
When you
want to
buy just a
few pounds
of Bronze
for
example,
you're
looking at
substantially
higher
prices.
Moreover,
once you
own
physical
Bronze
ingots,
make
absolutely
sure you
never sell
for the
spot price
of Bronze.
Because
it's hard
to get
ingot
grade
Bronze in
physical
form,
you've got
something
special on
your hands
and make
sure to
extract
the full
value when
you're
selling
and
understand
the
reverse
when
buying.
Bronze raw
ingot
source
selection
and prices
vary
greatly.
An example
of Silicon
Bronze
Alloy, In
small user
quantities
expect to
pay 14.00
to 18.00 a
pound.