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The metal used in our wrought iron products contains
.01% to .29% carbon. Almost all of our weathervanes,
wrought iron furniture, kitchen accessories like napkin and paper towel
holders,wrought iron wine
racks, wrought iron curtain
rods, and cabinet
hardware are hand bent and all are hand crafted.
Any products that have a silhouette are cut from sheets
of this low carbon wrought
iron on a laser cutting machine and
are then hand welded if needed, or hand bent, and then
powder coated.
Wrought
iron is a perfect metal for furniture,
weathervanes, wrought iron
wine racks, wrought iron curtain rods,
coat racks,
and other items that are meant to last for quite some
time partially because of its resistance to corrosion
and other weathering effects. It is both sturdy and
malleable, and so makes for one of the best metals to
be welded or shaped into furniture, wrought
iron curtain rods, and other various forms.
In the creation of furniture, wrought iron curtain
rods, wine or coat racks,
candle
holders, sconces,
napkin holders, and many, many more products, wrought
iron provides a unique and stylish look and
allows for a multitude of different design schemes.
If youre looking for an attractive weathervane
for your front yard, chances are its going to
be made of wrought iron, and for good
reason. Read the following information to get a better
idea about why we chose the material we did, and youll
come to appreciate the beauty and uniqueness of wrought
iron. After learning more about wrought
iron, browse our wrought iron curtain
rods, wrought iron furniture, wrought iron
wine racks, and more to find something to add a bit
of charm to your home!
Applications
Iron is the most used of all the
metals, comprising 95 percent of all the metal tonnage
produced worldwide. Its combination of low cost and
high strength make it indispensable, especially in applications
like automobiles, the hulls of large ships, and structural
components for buildings. Steel is the best known alloy
of iron, and some of the forms that iron takes include:
Pig
iron has 4%
5% carbon and contains varying amounts of contaminants
such as sulfur, silicon and phosphorus. Its only significance
is that of an intermediate step on the way from iron
ore to cast iron and steel.
Cast iron
contains 2% 3.5% carbon
and small amounts of manganese. Contaminants present
in pig iron that negatively affect the material properties,
such as sulfur and phosphorus, have been reduced to
an acceptable level. It has a melting point in the range
of 14201470 K, which is lower than either of
its two main components, and makes it the first product
to be melted when carbon and iron are heated together.
It is extremely strong, hard and brittle. Working cast
iron, even white hot cast iron, tends to break the object.
Carbon steel
contains between 0.5% and 1.5%
carbon, with small amounts of manganese, sulfur, phosphorus,
and silicon.
Wrought iron
contains less than 0.5% carbon. It is a tough, malleable
product, not as fusible as pig iron. It has a very small
amount of carbon, a few tenths of a percent. If honed
to an edge, it loses it quickly.
Alloy steels
contain varying amounts of carbon as well as other metals,
such as chromium, vanadium, molybdenum, nickel, tungsten,
etc.
Iron (III) oxides are used in the production of magnetic
storage in computers. They are often mixed with other
compounds, and retain their magnetic properties in solution.
Notable characteristics
Iron is the most abundant metal,
and is believed to be the tenth most abundant element
in the universe. Iron is also the most abundant (by
mass, 34.6%) element making up the Earth; the concentration
of iron in the various layers of the Earth ranges from
high at the inner core to about 5% in the outer crust;
it is possible the Earth's inner core consists of a
single iron crystal although it is more likely to be
a mixture of iron and nickel; the large amount of iron
in the Earth is thought to contribute to its magnetic
field. Its symbol Fe is an abbreviation of ferrum, the
Latin word for iron.
Iron is
a metal extracted from iron ore, and is hardly ever
found in the free (elemental) state. In order to obtain
elemental iron, the impurities must be removed by chemical
reduction. Iron is used in the production of steel,
which is not an element but an alloy, a solution of
different metals (and some non-metals, particularly
carbon).
The nucleus
of iron has the highest binding energy per nucleon,
so it is the heaviest element that is produced exothermically
through fusion and the lightest through fission. When
a very large star contracts at the end of its life,
internal pressure and temperature rise, allowing the
star to produce progressively heavier elements. When
iron is reached, the star will no longer produce sufficient
energy in its core, and a supernova will ensue.
Cosmological
models with an open universe predict that there will
be a phase where as a result of slow fusion and fission
reactions, everything will become iron.
History
The first signs of use of iron
come from the Indians; Sumerians and the Egyptians,
where around 4000 BC, small items, such as the tips
of spears and ornaments, were being fashioned from iron
recovered from meteorites. Because meteorites fall from
the sky some linguists have conjectured that the English
word iron, which has cognates in many northern and western
European languages, derives from the Etruscan aisar
which means "the gods".
Iron was
used in India as early as 250 BCE. The famous Ashoka
Pillar near Delhi is made of very pure iron (98%) and
has not rusted or eroded till this day. By 3000 BC to
2000 BC, increasing numbers of smelted iron objects
(distinguishable from meteoric iron by the lack of nickel
in the product) appear in Mesopotamia, Anatolia, and
Egypt. However, their use appears to be ceremonial,
and iron was an expensive metal, more expensive than
gold. In the Iliad, weaponry is mostly bronze, but iron
ingots are used for trade. Some resources (see the reference
What Caused the Iron Age? below) suggest that iron was
being created then as a by-product of copper refining,
as sponge iron, and was not reproducible by the metallurgy
of the time. By 1600 BC to 1200 BC, iron was used increasingly
in the Middle East, but did not supplant the dominant
use of bronze.
Axe of iron from Swedish Iron Age, found at Gotland,
Sweden.In the period from the 12th to 10th century BC,
there was a rapid transition in the Middle East from
bronze to iron tools and weapons. The critical factor
in this transition does not appear to be the sudden
onset of a superior ironworking technology, but instead
the disruption of the supply of tin. This period of
transition, which occurred at different times in different
parts of the world, is the ushering in of an age of
civilization called the Iron Age.
Concurrent
with the transition from bronze to iron was the discovery
of carburization, which was the process of adding carbon
to the irons of the time. Iron was recovered as sponge
iron, a mix of iron and slag with some carbon and/or
carbide, which was then repeatedly hammered and folded
over to free the mass of slag and oxidize out carbon
content, so creating the product wrought iron. Wrought
iron was very low in carbon content and was not easily
hardened by quenching. The people of the Middle East
found that a much harder product could be created by
the long term heating of a wrought iron object in a
bed of charcoal, which was then quenched in water or
oil. The resulting product, which had a surface of steel,
was harder and less brittle than the bronze it began
to replace.
In China
the first irons used were also meteoric iron, with archeological
evidence for items made of wrought iron appearing in
the northwest, near Xinjiang, in the 8th century BC.
These items were made of wrought iron, created by the
same processes used in the Middle East and Europe, and
were thought to be imported by non-Chinese people.
In the
later years of the Zhou Dynasty (ca 550 BC), a new iron
manufacturing capability began because of a highly developed
kiln technology. Producing blast furnaces capable of
temperatures exceeding 1300 K, the Chinese developed
the manufacture of cast, or pig iron.
If iron
ores are heated with carbon to 14201470 K, a
molten liquid is formed, an alloy of about 96.5% iron
and 3.5% carbon. This product is strong, can be cast
into intricate shapes, but is too brittle to be worked,
unless the product is decarburized to remove most of
the carbon. The vast majority of Chinese iron manufacture,
from the Zhou dynasty onward, was of cast iron. Iron,
however, remained a pedestrian product, used by farmers
for hundreds of years, and did not really affect the
nobility of China until the Qin dynasty (ca 221 BC).
Cast iron
development lagged in Europe, as the smelters could
only achieve temperatures of about 1000 K. Through a
good portion of the Middle Ages, in Western Europe,
iron was still being made by the working of sponge iron
into wrought iron. Some of the earliest casting of iron
in Europe occurred in Sweden, in two sites, Lapphyttan
and Vinarhyttan, between 1150 and 1350 AD. There are
suggestions by scholars that the practice may have followed
the Mongols across Russia to these sites, but there
is no clear proof of this hypothesis. In any event,
by the late fourteenth century, a market for cast iron
goods began to form, as a demand developed for cast
iron cannonballs.
Early
iron smelting (as the process is called) used charcoal
as both the heat source and the reducing agent. In 18th
century England, wood supplies ran down and coke, a
fossil fuel, was used as an alternative. This innovation
by Abraham Darby supplied the energy for the Industrial
Revolution.
Compounds
This heap of iron ore pellets
will be used in steel production. Common oxidation states
of iron include:the Iron(II) state, Fe2+, previously
ferrous is very common.
the Iron(III) state, Fe3+, previously ferric, is also
very common, for example in rust.
the Iron(IV) state, Fe4+, previously ferryl, stabilized
in some enzymes (e.g. peroxidases).
the Iron(VI) state, Fe6+ is also known, if rare, in
potassium ferrate.
iron carbide Fe3C is known as cementite.
[edit]
See also
iron oxide
Occurrence
The red appearance of this water
is due to iron in the rocksIron is one of the more common
elements on Earth, making up about 5% of the Earth's
crust. Most of this iron is found in various iron oxides,
such as the minerals hematite, magnetite, and taconite.
The earth's core is believed to consist largely of a
metallic iron-nickel alloy. About 5% of the meteorites
similarly consist of iron-nickel alloy. Although rare,
these are the major form of natural metallic iron on
the earth's surface.
Industrially,
iron is extracted from its ores, principally hematite
(nominally Fe2O3) and magnetite (Fe3O4) by reduction
with carbon in a blast furnace at temperatures of about
2000°C. In a blast furnace, iron ore, carbon in
the form of coke, and a flux such as limestone are fed
into the top of the furnace, while a blast of heated
air is forced into the furnace at the bottom.
In the
furnace, the coke reacts with oxygen in the air blast
to produce carbon monoxide:
6 C +
3 O2 ? 6 CO
The carbon monoxide reduces the iron ore (in the chemical
equation below, hematite) to molten iron, becoming carbon
dioxide in the process:
6 CO +
2 Fe2O3 ? 4 Fe + 6 CO2
The flux is present to melt impurities in the ore, principally
silicon dioxide sand and other silicates. Common fluxes
include limestone (principally calcium carbonate) and
dolomite (magnesium carbonate). Other fluxes may be
used depending on the impurities that need to be removed
from the ore. In the heat of the furnace the limestone
flux decomposes to calcium oxide (quicklime):
CaCO3
? CaO + CO2
Then calcium oxide combines then with silicon dioxide
to form a slag.
CaO +
SiO2 ? CaSiO3
The slag melts in the heat of the furnace, which silicon
dioxide would not have. In the bottom of the furnace,
the molten slag floats on top of the more dense liquid
iron, and spouts in the side of the furnace may be opened
to drain off either the iron or the slag. The iron,
once cooled, is called pig iron, while the slag can
be used as a material in road construction or to improve
mineral-poor soils for agriculture.
Approximately
1100Mt (million tons) of iron ore was produced in the
world in 2000, with a gross market value of approximately
25 billion US dollars. While ore production occurs in
48 countries, the five largest producers were China,
Brazil, Australia, Russia and India, accounting for
70% of world iron ore production. The 1100Mt of iron
ore was used to produce approximately 572Mt of pig iron.
Biological role
Iron is essential to all organisms,
except for a few bacteria. It is mostly stably incorporated
in the inside of metalloproteins, because in exposed
or in free form it causes production of free radicals
that are generally toxic to cells. To say that iron
is free doesn't mean that it is free floating in the
bodily fluids. Iron binds avidly to virtually all bio
molecules so it will adhere nonspecifically to cell
membranes, nucleic acids, proteins etc.
Animals
incorporate iron into the heme complex, an essential
component of cytochromes, which are proteins involved
in redox reactions (including but not limited to respiration),
and of oxygen carrying proteins hemoglobin and myoglobin.
Inorganic iron involved in redox reactions is also found
in the iron-sulfur clusters of many enzymes, such as
nitrogenase (involved in the synthesis of ammonia from
nitrogen and hydrogen) and hydrogenase. A class of non-heme
iron proteins is responsible for a wide range of functions
within several life forms, such as enzymes methane monooxygenase
(oxidizes methane to methanol), ribonucleotide reductase
(reduces ribose to deoxyribose; DNA biosynthesis), hemerythrins
(oxygen transport and fixation in marine invertebrates)
and purple acid phosphatase (hydrolysis of phosphate
esters). When the body is fighting a bacterial infection,
the body sequesters iron in the transporter protein
transferrin so it cannot be used by bacteria.
Iron distribution
is heavily regulated in mammals. The iron absorbed from
duodenum binds to transferrin, and carried by blood
it reaches different cells. There it gets by an as yet
unknown mechanism incorporated into target proteins.
[1].
Good sources
of dietary iron include meat, fish, poultry, lentils,
beans, spinach, tofu, chickpeas, black-eyed pea, strawberries
and farina.
Iron provided
by dietary supplements is often found as Iron (II) fumarate.
The RDA for iron varies considerably based on the age,
gender, and source of dietary iron (heme-based iron
has higher bioavailability)[2]. Also note the section
below on precautions.
Isotopes
Iron has four naturally-occurring stable isotopes, 54Fe,
56Fe, 57Fe and 58Fe. The relative abundances of the
Fe isotopes in nature are approximately 54Fe (5.8%),
56Fe (91.7%), 57Fe (2.2%) and 58Fe (0.3%). 60Fe is an
extinct radionuclide which had a long half-life (1.5
Myr). Much of the past work on measuring the isotopic
composition of Fe has centered on determining 60Fe variations
due to processes accompanying nucleosynthesis (i.e.,
meteorite studies) and ore formation. The isotope 56Fe
is of particular interest to nuclear scientists as it
represents the most stable nucleus possible. It is not
possible to perform fission or fusion on 56Fe and still
liberate energy. This does not hold true for any other
element. In phases of the meteorites Semarkona und Chervony
Kut a correlation between the concentration of 60Ni,
the daughter product of 60Fe, and the abundance of the
stable iron isotopes could be found which is evidence
for the existence of 60Fe at time formation of solar
system. Possibly the energy released by the decay of
60Fe contributed, together with the energy released
by decay of the radionuclide 26Al, to the remelting
and differentiation of asteroids after their formation
4.6 billion years ago. The abundance of 60Ni present
in extraterrestrial material may also provide further
insight into the origin of the solar system and its
early history. Of the stable isotopes, only 57Fe has
a nuclear spin (-1/2). For this reason, 57Fe has application
as a spin isotope in chemistry and biochemistry.
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