Aluminum is one of the popular metals in the world. It is notorious for being lightweight, having a high strength-to-weight ratio, and being corrosion-resistant. However, one of the most important characteristics of aluminum that is debatable is that it conducts electricity. Therefore, how do you answer the question, Is aluminum an electrical conductor? This is where we come to the answer: yes, aluminium can conduct electricity, but not as well as copper, which has been the metal of choice when creating an electrical system. 

This paper shall discuss the electrical conductivity of aluminum, its use in the electrical industry, and the benefits and limitations of using it in the electrical industry.

What does Electrical Conductivity mean?

We will first consider what electrical conductivity is prior to saying whether aluminum is an electrical conductor or not. The capacity of a material to permit electric current is called electrical conductivity. This depends on the number of free-moving electrons in that material. Metals, generally, have very free electrons which can flow easily within their atomic structure, so they are good conductors.

The measuring unit of the electrical conductivity of a given material is noticeable in siemens divided by meter (S/m). The greater the resistance, the less the feasibility of the electricity to pass through. Highly conductive materials such as copper and aluminum find use in several electrical applications such as power supply, power transmission, wiring and circuits.

Does Aluminum Conduct electricity?

Yes, aluminium is many times conductive than copper. Aluminum is regarded as a good conductor when looking at the conductivity of metals, though its electrical conductivity is only about 61 per cent of copper. This implies that copper will provide a greater current to flow through a given size of wire.

This notwithstanding, the fact that aluminum has a relatively high conductivity makes it applicable in most electrical applications, particularly where weight and cost are critical considerations. The resistivity of aluminum is not as high as that of many other materials; that is, aluminum can also conduct electricity, but with relatively less resistance.

How Aluminum Conduces Electricity?

Electricity is conducted in an Aluminum because of the flow of free electrons through the structure of the atoms. These free electrons are only weakly connected to the atoms of the metal and can easily move once an electric field is present. As the material allows the electrons to pass through it, an electric current will be created.

Aluminum also possesses quite a high amount of free electrons, which means it is also a decent conductor of electricity, but not as efficient as copper. It is approximately 61 times less electrically conductive than copper, so it is slightly more resistant to the flow of electrons.

The conductivity of aluminum is also decreased by an increase in temperature due to the increased vibration of atoms in the metal, which increases the resistance. Moreover, oxide layers of non-conductivity develop on the surface of aluminum, and this may decrease conductivity where joints are made. This layer of oxide that is formed should be controlled because it would impair good conductivity, particularly in electrical contacts.

Electrically Conductive Aluminum Grades 

Aluminum is an electrical conductor, and its level of conductivity also depends on the grade, since various grades contain different purities and alloying metals. The correlation between the type of aluminum grade and its conductivity is imperative when choosing the right type of aluminum that fits certain electrical applications.

1. PURE Aluminium ( 1100 Grd )

Aluminum grade 1100 can be regarded as one of the purest aluminums with a purity level of 99 per cent and above. This purity is high, which leads to good electrical conductivity electrically hence it would be good in areas that require electrical conductivity and performance best, like wiring and connections to electricity.

• Elektrische geleidbaarheid: Approximately 61 per cent of that of copper.
• Toepassingen: It is used in power cable systems, electrical conductors and other devices where high conductivity and low resistance are essential.

2. Aluminum Alloy 1350

Aluminum Alloy 1350 is another high-purity aluminum, only that it is combined with minute quantities of copper to enhance its strength as well as other properties. This grade is conductive at a notch lower level than 1100-grade aluminum has but goes a long way in giving good performance in electrical functions too.

• Electric Conductivity: About 61 per cent of the conductivity of copper, which is like 1100 grade aluminium.
• Toepassingen: It is widely used in wires, conductors and transformer, particularly in high-voltage electrical systems.

3. 6063 Aluminum Alloy

Aluminum grade 6063 is a medium-strength alloy and is normally used for structural purposes such as extrusions and frames. It has more alloying materials like magnesium and silicon, which add to the mechanical strength, thus making it less conductive electrically than 1100 and 1350 grade aluminum.

• Elektrische geleidbaarheid: Conductivity of copper is 50-55 per cent lower, with additional alloying effects of the elements.
• Toepassingen: It is mainly applied in architectural extrusions, window frames, and aerospace constituents. Although it is not as conductive as the purer grades, it finds some uses in areas where the strength and formability rather than conductivity are of importance.

4. Aluminum Alloy 1050

Aluminum Alloy 1050 is also high-purity aluminum, except that it has a slight presence of iron; hence, its conductivity is less than that of 1100-grade aluminum. It is, however, good in its electrical conductivity for various applications.

• Elektrische geleidbaarheid: The rate of electrical conductivity is 99.76 % of that of copper, the equivalent of 1100-grade.
• Toepassingen: Electrical cables, wires, and battery connectors in which high conductivity is the factor, yet in which the cited mechanical strength is not a major issue.

5. Aloy 6061 aluminum

What makes this 6061-grade aluminum alloy popular is its good mechanical properties and versatility. To make it strong, it is alloyed with magnesium and silicon, causing a moderate loss in conductivity.

-Electrical Conductivity: approximately 45-50 per cent of the conductivity of copper.

Application: Should be commonly found in structural parts, automobile parts, and equipment used in the high seas, where electric conductivity was not of much significance, but strength and resistance to corrosion were.

Does Electrical Conductivity Get Affected by Aluminum Finishing?

The electrical conductivity of aluminum may be greatly influenced by the aluminum finishing, and this is determined by the finish one applies to the metal. The conductive property of aluminum can be changed with different surface treatments: oxide layer formation, anodizing, coating, polishing, etc.

1. Formation of oxide layer

In the presence of air, such as through the oxidation process, aluminum forms a thin layer of oxides (Al 2 O 3 ). Although this oxide layer offers protective cover to corrosion, it is not conductive. This implies that this oxide film on the point where the electricity is connected can raise the resistance, thereby compromising the overall conductivity of aluminum. The efficiency of electrical activities at high performance can be lost because of the existence of this oxide layer. To achieve good conductivity, such an oxide layer must be eliminated or limited at contact sites, or surface treatments are supplied to avoid oxide deposition.

2. Anodiseren

Where aluminum is involved, anodizing is a process aimed at deliberately making the oxide film thicker. Though it enhances corrosion resistance and improves the aesthetic finish of the surface, anodizing further renders the surface more insulating. This considerably decreases the conductivity of the aluminum that making it inappropriate for applications that involve the use of electrical current. But in certain applications, such as those with aesthetic importance, the anodic coating is not removed because of the protective effect, which is a major threat. Anodizing cannot be optimal in the conductive applications unless a purposeful removal of the oxide layer is planned at the points of connection.

3. Coatings and paints

Aluminum is coated and painted to offer extra protection against the environmental elements and enhance the look of appearance. Yet the vast majority of coatings (especially normal paint) are insulating and form electrical conductivity barriers. Coatings have the effect of reducing the electrical conductivity of the metal by a large margin in cases where the coating is applied. In the case of aluminum in electrical system application,s it should be remembered that the parts with which electrical contact is made should not be coated, or in special cases, it might be desirable to use conductive coating in particular situations.

4. Surface Polishing

One of the finishing methods that is used is surface polishing in order to have a clean and smooth surface of aluminum. Mechanically, the polishing in the case of electrical conductivity is the process that improves the property in terms of electrical conductivity to offer a cleaner contact surface. Polished aluminum surface permits greater efficiency in electrical connection, lowers resistance and enhances performance in electric systems. But when the polishing is done too much, it can lead to the loss of material, which can be a problem for the integrity and size of the aluminum in some applications. Consequently, polishing is only to be used to achieve the desirable balance between conductivity and the strength of the material.

Why is Aluminum Being Used in Electricity?

Even though copper is electrically conductive compared to aluminum, it has not led the electrical industry to escape using aluminum. The causes of this are:

1. Cost-Effectiveness

A cheaper price is one of the main advantages of aluminum application in electronics. Unlike copper, aluminum is cheaper; in fact, its price is approximately one-third the cost of copper. This affordability factor will make aluminum a great option when it comes to large-scale electrical installations because an ample quantity of material is needed.

2. Lichtgewicht

Aluminum is also very light compared to copper, and its density is approximately one-third of copper. This is what makes it suited in areas where weight is an issuee like in overhead power transmission lines. The transport cost is lower due to the lightweight of aluminum and the installation of the same becomes easy.

3. Corrosiebestendigheid

When in the open air, aluminium also naturally develops a thin protective oxide coating that covers the surface. This oxide film serves as a sealant which cannot be further oxidized, and thus, aluminum is an extremely corrosion-resistant material. This is advantageous, especially to electrical systems that are outdoors, as weather factors and humidity can easily corrode other metals such as copper.

4. Strength-to-Weight Ratio

Aluminum has a great strength-to-weight ratio,, which implies that although it is lightweight, it can offer great structural strength. This aspect makes aluminum a beautiful option in almost all electrical matters like cables, transmission lines and even when constructing electrical equipment.

Strength of Aluminum and Copper Compared: Electrical Conductivity

As has been stated above, the electrical conductivity of the aluminum is approximately 61 per cent of copper. Nevertheless, the conductivity difference is not as huge as it may seem. In the case of many large-scale applications, e.g. power transmission, savings in cost and weight afforded by aluminum offset its slightly reduced conductivity. With that being said, when it comes to high electrical performance then copper would still be the better conductor.

A comparison Aluminum and Copper:

Although copper is more conductive, the disparity in performance is normally explained by setting up a larger cross-sectional aluminum cable to carry the same quantity of electricity in a copper cable of a smaller cross-section. That is why overhead power transmission wires and other large-scale electrical installations usually employ aluminum cables.

The comparison of Aluminum with other conductors

When it comes to comparing the aluminum to other electrical conductors such as copper and silver, its performances are said to be satisfactory many times, but not well use in a high-performance system.

Uses of Aluminum in Electricity

Aluminum finds application in very diverse electrical products, especially where those mentioned features benefi:; low cost, low density, and corrosion resistance.

1. Power transmission lines

The most common application of aluminum is in overhead power transmission lines, in which its low weight and high conductivity value make it suitable for long-distance electricity transmissions. The use of power lines comprising aluminum is cheaper to lay and maintain when compared to copper, and due to their lightweigh,t they are easily handled in terms of installation of the lines.

2. Electrical Wiring /Cables

Aluminum wiring is commonly utilised in residential and commercial construction, particularly on circuits that have low and moderate-level capacities of electrical loads. Copper wire can still be employed in high-performance circuits, but aluminum can be applied in large installations where cost and weight play a vital role.

3. Grounding Wires

Grounding wires are also made of aluminum, since there is a need to provide a safe path in which the electrical current can flow in case of a fault. Grounding plays a fundamental role in the safe dispel of any excessive electrical current onto the ground so that no equipment is damaged and the chances of electrical fires are minimized.

4. Electric Motors and Apparatus

Electric motors and transformers have aluminum that comprises the winding material. The metal is lightweight, is relatively strong, and possesses good conductivity, which makes it a considerably great option when applying it to an extensive variety of industrial and commercial applications

Issues and Solutions to Problems with Aluminum Conductivity

As much as aluminum is an appropriate conductor, it also comes with certain issues which should be resolved when employed as a conductor in an electrical system.

1. Higher Resistance

The biggest disadvantage of aluminum is that it is electrically conductive than copper. This implies that, when equal current flows, more heat and a drop in voltages in the aluminum wire occur. This ,in a few instances, necessitates the use of larger aluminum conductors to deliver the same performance as copper wires.

2. Connection and Oxidation problems

Aluminum will easily be oxidized, particularly, joints. On one hand, when aluminum is covered with an oxide layer, it is corrosion resistant; on the other hand, the oxide layer can layer itself as an electric insulator, creating higher resistance, isolating the junctions. This may cause overheating, malfunctioning and in worst situations, electrical failure. In an attempt to curb this, during installation, special attention should be demanded such that the right connections are made and no corrosion can occur at the joints.

3. Mechanical Strength

Even though aluminum has an excellent strength-to-mass ratio, it is still less robust than copper and may be susceptible to mechanical damage, particularly in high-stress/ vibration conditions. In high-stress applications, the aluminum wires are usually reinforced with steel or other materials.

Conclusie

However, it can be concluded that indeed aluminum conducts electricity, but it is also a commonly used material in the electrical industry because of its good conductivity, economics, the fact that it is light weight, and resistance to corrosion. Although it is not as conductive as copper, it is cheap enough and possesses other beneficial characteristic,s thus can be used as an alternative to copper in most electrical applications.

Aluminium is especially practical on large-scale endeavours like power transmission and electrical wiring, where the price and weight advantages greatly outweigh a tendency of lower conductivity. Nevertheless, its challenges, which should be put into consideration by engineers and electricians when designing and laying aluminum-based electrical systems, are its increased resistance and oxidation.

Nevertheless, aluminum is a vital material used in the electric industry, and its usage will only rise since more efficient and affordable electrical infrastructures are demanded all over the world.