Since its industrialization in the early s, Aluminum has become one of the most commonly used metals in various industries. Its lightweight and relatively high strength make it perfect for numerous applications.
If you want to learn more, please visit our website Jinding.
In this article, well explore some common uses for Aluminum sheets, the different types, and why its used over other materials.
After the material is refined and alloyed with other elements, sheet Aluminum is made through a process involving the rolling and flattening of cast ingots. The process is tightly controlled and produces consistent thicknesses.
The thicknesses available range from 0.020 up to 0.19, and in a multitude of different grades and tempers. Different thicknesses are preferred for different applications.
The temper of the Aluminum sheet is the state of heat treatment it is currently in. This affects the strength and workability of the material. Not all Aluminum grades can be heat-treated.
After steel and its variations, Aluminum is the most commonly found metal in the industry. It has multiple beneficial properties when compared to steel or stainless steel, these include:
At around one-third of the weight of steel, Aluminum can be used to produce structures and components that are much cheaper to transport, better to use, or safer to lift when compared to steel or stainless steel.
In terms easier to visualize, an 8 x 4 sheet of Aluminum in 1/8th weighs 25kg, a sheet of steel of the same dimensions weighs over 70kg.
Despite its low density, Aluminum is incredibly strong, and can be stronger than steel and stainless steel per pound.
If a beam constructed of steel was replaced by one from Aluminum, it could be half as heavy whilst still able to support the same load. Many safety-critical components for aircraft, cars, motorbikes and bicycles are made from Aluminum.
Another big benefit of Aluminum is that it does not rust in the same way Steel does, this is due to the lack of Iron in Aluminum alloy. Aluminum does oxidize however, but only in specific circumstances and does not cause the same structural issues as with steel.
Because Aluminum does not rust, there are large savings available in not having to paint or finish the parts to prevent corrosion. This also means parts can last longer without the need for repainting or replacement due to corrosion.
Aluminum is more expensive than steel, but generally slightly cheaper than stainless steel. However, as we just discussed, the end product costs of Aluminum can match steel components because they dont need finishing to be protected from the elements.
Here at Metals Supermarkets, we stock multiple grades of Aluminum sheets, all at very reasonable prices. Check out our Aluminum grades and stock here for exact pricing and availability or visit your closest store.
The workability of Aluminum is one of its greatest strengths, thanks to the wide variety of grades and heat treatment processes, there is almost no process that cannot be adapted to work efficiently with Aluminum sheets.
Alongside great weldability, Aluminum can be bent, machined, forged, rolled and laser cut with great success, as long as the grade is specified correctly.
Like all metal alloys, Aluminum comes in a multitude of grades, each with slightly different alloying compositions and therefore differing mechanical properties. The main types of Aluminum are listed below, Metal Supermarkets can supply all of these grades.
Once you start to look for it, its easy to find Aluminum sheet materials in almost any environment, from consumer electronics and packaging to aerospace components.
The International Aluminum Institute (IAI) predicts the global demand for aluminum in the electronics industry will rise from 8 million tons to 12 million tons in the coming years. However, the demand for copper is expected to reach the same level (around 13 million tons). Which begs the question, just how good of a conductor is aluminum?
Understanding the electrical conductivity of aluminum is essential for designers, product developers, and companies who want to benefit from the cost-effective nature of aluminum or its lightweight properties.
In this blog, well cover aluminum conductors, the electrical characteristics of aluminum, and their possible use as an alternative to copper and other conductive metals.
Before we delve into the conductivity of aluminum and its electrical properties, here are some basic facts about aluminum.
This background knowledge will help you understand the properties table and make comparison between aluminum conductors easier.
Aluminum is a metal element in the periodic table with the atomic number 13. It is one of the most abundant metals found on earth. Unfortunately, aluminum does not exist in its pure form and has to be produced at an industrial scale from its oreBauxite.
Aluminum conductor is widely used in the electronics industry, and it is the 4th most conductive metal after silver, copper, and gold; in that order. Many alloys of aluminum have different conductivities.
Aluminum is lightweight, ductile, and corrosion-resistant, which helps it in electrical applications because it can be turned into wires and quickly melted for soldering.
So whats the significance of the number 13? It represents the number of electrons in an atom of aluminum and their arrangement in electron orbitals. Later, we will find that it is these electrons that contribute towards aluminums conductivity.
Conductivity tells you how well a metal can conduct electricity. It is a measure of a materials tendency to conduct electrical current.
Conductivity is measured in Siemens (S) per meter (m). For aluminum, a known current is passed through the aluminum sample, and the voltage drop is measured using probes.
This can be used to calculate the conductivity of aluminum metal using a formula.
Aluminum is one of the best electrical conductors. It is just behind pure copper in terms of conductivity. Pure aluminum conductor has an electrical conductivity of 33.3 x 107 S/m.
To easily understand conductivity, it is often compared to that of pure copper. Pure copper is the best electric conductor behind silver. Which, for economic reasons, is not viable to use as a conductor at an industrial scale.
The International Annealed Copper Standard (IACS) gives a comparative reference for conductivity. Aluminum is 61% IACS, meaning it has an electric conductivity that measures 61% to that of copper.
Aluminum is widely used in electrical equipment because of its cost-effectiveness and low electrical resistance. Aluminum weighs about 30% lighter than copper, making it ideal for overhead power cables.
Aluminum is such a good conductor of electricity that transmission lines are mostly made of aluminum, and the electric current coming to your house comes via aluminum conductors.
If youre a designer understanding how aluminum conducts electricity can help you decide between aluminum alloys and other metals for your project.
Aluminum can conduct electricity because of its structure and atomic bonding.
This section covers how aluminum can conduct electricity.
Background About Current
At the most basic level, youd think current is a measure of electricity. Thats not entirely true. Current is the rate at which the charge passes through a point inside a loop.
To understand how aluminum conductors work, you need to understand charge, which is a positive or negative ion or electron.
Aluminums Conduction
Aluminum atoms are made of protons and neutrons, tightly held in the core, and surrounded by electrons.
When an aluminum atom loses an electron, it is called an aluminum iona positively charged aluminum ion.
Aluminum is made of many of these atoms, which are tightly packed together and have their outer electron as free electrons. They are not held tightly by the core of the aluminum atoms and can move around the aluminum.
To be specific, aluminum atoms have 13 electrons and 13 protons. This is why it is marked 13 on the periodic table. Arranging these 13 electrons in orbitals results in 3 electrons in its outer shell, which experience weak attraction from the nucleus.
Aluminum and other metals are surrounded by a sea of electrons that can move freely. Whenever theres a potential difference across the ends of an aluminum piece, these conduction electrons can move in the direction of polarity (positive or negative).
This movement of free electrons makes aluminum conduct electricity, and a measure of the rate at which these electrons pass through a point is current.
How Does Aluminums Conductivity Compare To Other Metals
The conductivity test on aluminum can also identify the correct grades of aluminum and determine if a heat treatment process has been done on aluminum. A heat-treated aluminum sample has a different conductivity than untreated aluminum.
There are defined International Annealed Copper Standard ratios for different alloys, and treatment methods.
Theres conductivity variation from aluminum alloy to aluminum alloy and between aluminum and metals. This table from Researchgate compares the conductivity of aluminum with known metals.
Rank
Metal
Electrical conductivity (
S
m
-1
)
1
Silver
66.7
1
0
6
2
Copper
64.1
1
0
6
3
Gold
49.0
1
0
Contact us to discuss your requirements of Aluminium Series. Our experienced sales team can help you identify the options that best suit your needs.
6
4
Aluminum
40.8
1
0
6
5
Rhodium
23.3
1
0
6
6
Zinc
18.2
1
0
6
6
Nickel
16.4
1
0
6
7
Cadmium
14.7
1
0
6
8
Iron
11.2
1
0
6
From the table, you can quickly tell Iron is not the top choice for electrical applications. Iron is mainly used in its stainless steel form and is one of the worst conductors.
But why is copper ranked so high in terms of conducting electricity?
For many reasons, copper is still the primary choice for electrical conductors. It is more ductile, has a golden-brown finish that can help aesthetics, and has better strength and hardness. Yes, it is an excellent conductor of electricity and better than aluminum.
Copper is a better electrical conductor than aluminum because of its resistance to electric current.
Resistance is a measure of opposition to current flow. Materials with high resistance, like plastic or rubber, are called insulators. All materials have resistance, but in metals, it is extremely small.
Resistance depends on dimensions and a material property called resistivity. If you consider copper conductors with equal length and area as their aluminum counterparts, youll find copper conductors to have high conductivity. This is because copper has a smaller resistivity than aluminum.
In experimental terms, copper is a good conductor because its free electrons are less likely to experience a phenomenon called phonon collision. This is when vibrating atoms produce a mechanical form of energy that interferes with electron movement. As a result, aluminums free electrons, despite being in a higher concentration than copper, experience more phonon collisions and scatter about, or in other words, contribute to resistance to electric current.
In its raw form, aluminum has a low resistance to electric current. However, thats not how aluminum is used. Most applications of aluminum require a specific treatment, addition of impurity, or formation of alloys.
Aluminum alloys are classified in grades. Aluminum grades start from series and range to series. You can read more about aluminum grades and their best applications here.
series aluminum is the purest and most conductive. series are alloys of copper, and series are magnesium-silicon and aluminum alloys.
Theres no steadfast rule for guessing the conductivity of aluminum grades. Instead most data is experimental.
EC-grades of aluminum conduct electricity best. This is a series aluminum ( Al) with good electrical and thermal conductivity. EC refers to electrical grade. It has approximately 61 % IACS conductivity.
Other grades of aluminum like AA- and AA- are also good conductors with applications including aluminum wire and construction.
Aluminums surface finish can change its electrical properties. Simply put, if you use aluminum for electronic devices and end up with some form of surface alteration, it can diminish aluminums conductivity. Hence, defeating your original purpose of having a good conductor.
Aluminum has a natural aluminum oxide layer that is extremely thin. Many people want their products to last longer and perform anodizing which can increase its corrosion resistance by growing the oxide layer.
However, the aluminum oxide layer does not conduct electricity because it has no free electrons. This way, youre surrounding aluminum with an extremely poor conductor of electricity.
Powder coating, heat treatment, paint, and plastic coatings all affect aluminum conductors differently. As mentioned, their conductivity ratio to IACS is sometimes used to identify which heat treatment has been done on aluminum.
For example -T4 is 44 % IACS, while -T6 is 47% IACS. T4 and T6 are different types of heat treatment processes for the same aluminum alloy.
There are many reasons to use aluminum as an electrical conductor. However, its properties make it ideal for a few particular purposes in the electrical industry.
Wiring and Cabling
Aluminum wire is often used in overhead transmission lines because aluminum has a low density than copper. This means it is lighter in weight than copper.
Using aluminum wire over copper wire results in three times lighter weight, which helps prevent these cables from sagging. So, for a 1 m aluminum line weighing around 6 Kg, an equivalent copper conductor of 18 Kg would be required.
Aluminum offers around 60% 64% IACS, which is an excellent conductivity compared to its weight and abundance.
Aluminum is also more cost-effective to produce and easier to handle than copper.
While houses and construction sites use copper wires more, industries and significant power generation sources employ aluminum wires. The series aluminum wires have excellent conductivity and are used in electrical wiring of residential buildings.
Electrical components
Aluminums electrical conductivity is also used to make electrical components from small connectors to large electronic devices where its lightweight properties can be used.
A rapidly growing market for aluminum is electric cars, where the casings for the motor and the electric motor use aluminum to keep the heavy battery from adding more weight.
Heatsinks
Its thermal conductivity makes it ideal for heatsinks and is often found in computers and processing units. They are also used in lamps and amplifiers.
Aluminum heatsinks essentially increase the area of heat dissipation which results in rapid cooling and quicker heat transfer away from the electronic device.
Conclusion
Aluminum is one of the best conductors with ever-expanding uses. It has a light weight, low cost, and ready availability worldwide, making it ideal for many electrical uses.
Aluminum is one of the two commercially used conductors besides copper. Despite being slightly less conductive than copper, its lightweight makes it extremely useful in many industries, from automobiles to power grids.
The conductivity of aluminum is so high that a simple aluminum foil can act as an electrical conductor. However, the conductivity of the foil will be much less than that of a wire or pure aluminum.
This is because the surface features of aluminum affect its conductivity. Painting, coating, or anodizing can significantly decrease conductivity. So, you should consider the final application of your aluminum product before considering any surface treatments.
Want more information on Coated Aluminum Coil? Feel free to contact us.