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Different types of metals and their classifications

There are various types of metals out-there suitable for specific applications. Even though metals are made by mining ore from within the earth. They are extracted out of rocks in a large-scale industrial process. Leaving that aside, our purpose here is to discuss the different types of metals and their functions.

But before that, different metals have one or more mechanical properties such as hardness, ability to resist repeated stress which is known as fatigue strength, ductility, and malleability. These properties are often attributed to defects or imperfections in their crystal structure.

types of metals
Various angle iron profiles and steel rods kept in storage shelves in a steel shop.

Read more: Different Types of Nonferrous Metals and their Uses

Types of metals and their classifications

Metals can be classified according to the following:

  • Iron content
  • Atomic structure
  • Magnetic and non-magnetic metals

Classification by iron content:

Iron content is the common way of classifying different types of metals. Metals that contain iron are known as a ferrous metal. The iron-type imparts magnetic properties to the material and also make them prone to corrosion when exposed to moisture.

On the other hand, metals that do not have any iron content in them are known as non-ferrous metals. They do not have any magnetic properties. Examples of non-ferrous metals include aluminum, lead, brass, copper, and zinc.

Classification of metals according to their atomic structure:

Metals may also be classified based on their atomic structure stated in the periodic table. They may be known as alkaline, alkaline earth, or transition metals belonging to the same group that behaves similarly when reacting with other elements. That is to say, they have similar chemical properties.

Classification according to magnetic and non-magnetic metals:

Another best way of differentiating metals is checking how they react to magnets. In fact, it’s highly possible to different metal types as magnetic and non-magnetic, since ferromagnetic metals attract well and strong to magnets. On the other hand, paramagnetic ones show weak interactions with magnets. Lastly, there is a group of metals that shows weak repulsion to magnets.

Now let dive into popular types of metals and their properties.

Metals available out there share some similar mechanical properties, but when closely look, one must have a slightly different one from the other. there are possible ways of tweaking the properties of metals to get the desired property.

There are things to be considered when selecting metal for a particular application. These factors may include:

  • Melting point
  • Cost, ease of machining
  • Space available
  • Sufficient safety factor
  • Temperature coefficient
  • Density, and
  • Thermal and electrical conductivity.

Read more: Everything you need to know about sheet metals

Types of metals

Iron

In our life today, the implementation of iron has become part of civilization since 5 percent of the earth’s crust is iron. This is to say, metals are so much easy to find. Pure iron is said to be an unstable element, it reacts with oxygen in the air to form oxide. This is the first opportunity of iron.

Iron is extracted from its ores using a blast furnace, at its first stage of producing pig iron is achieved. Although it can be further refined into pure iron. The iron often ends up in steel and other alloys.  Ferrous metals are almost 90 percent of manufactured metals.

Pure irons are stronger than other metals but do not contain often required properties. Pure irons are not resistant to corrosion, which is one basic property needed. Keeping iron from corroding, some twerking must be performed which will cost more money and energy.

iron

Secondly, pure irons are extremely heavy due to their high density. Their applications on structures make it harder to build and maintain. To make pure iron much beneficial, carbon must be added to the iron. The mixture of iron and carbon to some specified limit is known as carbon steel, which is much of a benefit. Adding carbon to iron makes iron much stronger, some other great characteristics are also gained. This is when you need to learn about steel.

Steel

Steels are metal with high tensile strength and have a high strength-to-weight ratio, which means more strength per unit mass of steel. This is why they serve excellently as a building material. Using steel, smaller and strong components can be obtained. Steel is extremely durable, that is, it can last longer and withstand external factors better than other alternatives.

Additionally, steels are ductile and can be shaped into different required forms without losing their properties. Based on the iron content, steels are classified into three categories.

carbon steel

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Classification of carbon steel

Below is the classification of steel according to its iron content.

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·         Low carbon steel:

Low carbon steel which is also known as mild steel contains up to 0.25% carbon in iron. It’s often used for tubing moderate pressure applications. It is also common in construction work as reinforcing bars and I-beam made with low carbon steel. Generally, low carbon steel is used in any applications that require a high amount of steel without forming or bending. Ship’s hall is a good example.

·         Medium carbon steel:

Medium carbon steel contains about 0.25% of carbon. It also offers high tensile strength and ductility. This is why they are mostly used for gears and shafts, railway wheels and rails, steel beams in buildings and bridges, etc.

·         High carbon steel:

High carbon steel contains more than 0.6% of carbon. Unlike the previously listed ones, this steel is more brittle and harder. It’s used in applications like chisels and some other cutting tools because it offers great qualities including hardness and good resistance to material wear. It also serves well in presses and is used for manufacturing drill bits.

The above-mentioned types of steels are commonly called carbon steel because they contain some elements to enhance their properties. For example, chromium is added for corrosion resistance, or manganese is included to improve hardenability and tensile strength.

Read more: Properties and Composition of Pig Iron

Alloy steel:

These types of metals have multiple added elements to improve their various properties. Other metals like manganese, copper, silicon, titanium, nickel, and aluminum may be added in different proportions.

alloy steel

Alloy steel has better hardenability, corrosion resistance, weldability, ductility, and formability. it is widely used in bearings, heating elements, electric motor, springs, pipelines, gears, etc. below are the types of alloy steel.

·         Stainless steel:

Stainless steel contains a high amount of chromium, which makes it 200 times more corrosion resistant than mild steel. This makes it ideal for kitchen utensils, piping, dental and surgical equipment, etc. it does not require coating since its surface finish is appealing.

·         Tool steel:

Tool steel is used for making cutting and drilling tools since their high hardness makes them perfect for such tasks. these types of steel contain molybdenum, vanadium, cobalt, and tungsten, which serve as constituent metals.

Read more: different between welding and brazing joining process

Types of non-ferrous metals

Below are the various types of non-metals used in industries.

Aluminum:

Aluminum is gotten from its ore bauxite, having a light, strong, and have good properties. It is the most widespread metal on earth due to its good properties such as durability, lightweight, corrosion resistance, good electrical conductivity, ability to form alloys with metals, non-magnet, and ease to machined.

aluminium

Copper:

Copper are types of non-ferrous metals that can never be left behind. It has been in existence for a long because it’s easy to form and still in use in industries today. Copper does not occur in nature in its pure form. It’s extracted and smelted from ore.

The copper types of metals are the best good conductor when compared with others except for silver. this is why it is used as a conductor in an electrical circuit. Also, kitchen utensils are often made with copper due to their excellent heat conductivity.

copper metals

Lead:

Lead is a corrosion-resistant non-ferrous metal and it’s highly machinable. It’s used as an anti-locking agent in gasoline and can be used for piping and paint in some cases. Lead is still common in ammunition, car batteries, radiation protection, cable sheathing, lifting weights, etc.

lead

Brass:

Brass is an alloy of copper and zinc of appreciable amount depending on the electrical and mechanical properties the metal requires. It also contains some amount of other metallic elements like aluminum, lead, and manganese.

These types of metals are used for low friction applications such as plumbing, musical, bearings, locks, instruments, tools, and fittings.  Brass is of safety benefit to applications to prevent sparks and can be used in flammable environments.

brass non ferrous metal

Titanium:

Titanium is a great type of engineering metals due to it being lightweight and strong. It also has high thermal stability even at temperatures as high as 480 degrees Celsius. Because of these properties, it’s used in aerospace industries, military equipment, and medical applications due to its corrosion resistance. Finally, titanium is used in the chemical and sporting goods industry.

titanium metals

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Bronze:

Bronze is an alloy of copper, but it contains tin rather than zinc. Other elements like manganese, phosphorus, silicon, and aluminum may be added to improve their properties to suit a particular application. Bronze is hard, brittle, and capable of resisting fatigue. It also has good electrical and thermal conductivity and corrosion resistance.

These types of non-ferrous metals are used to make mirrors and reflectors. It’s also used as an electrical connector because of its conductivity. It’s also used in submerged parts and ship fittings due to its corrosion resistance.

bronze

Zinc:

Zinc are popular types of metals used in the medical and industrial fields. Its primary use is to galvanize steel by protecting it from corrosion. It’s also used in creating die castings for the electrical, hardware, and automobile industry. Because zinc has low electrochemical potential, it’s used in marine applications to prevent corrosion of other metals through cathodic protection. Sacrificial zinc anodes may protect valves, tanks, and pipelines.

zinc non ferrous metal

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Conclusion

Metals today are something we cannot do without, in fact, it’s part of human civilization since there are discoveries on them. in this article, we’ve explained the various types of ferrous and non-ferrous metals and also mentioned their classification.

I hope you enjoyed the reading, if so, kindly comment and share with other technical students. Thanks!

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