Whether it is a home appliance or crucial equipment of industry, Metals have always been the building blocks of conventional machines and big structures. With the evolution of humankind’s knowledge, the constant development because science and engineering have opened new doors to material discoveries and their properties optimization. Due to which there is a vast expansion in the metal industry too. Here we take a look at the most common types of metals, their basic properties, and uses.
As we have discussed in our articles about CNC and Welding each material is unique. However, most metals are ductile, lustrous (shiny), malleable, and are good conductors of heat and electricity. In this article, you will find all the essential properties and details of metals that you should know as a fabricator.
Contents
Iron (Ferrum)
Iron, being the most abundant metal on Earth and the sixth most common metal in our universe, has great importance in our metal industry. About 5% of the Earth’s crust is Iron. It is cheap and is used in almost every industry. Although it is not present in its pure form but as a compound such as Iron oxide, so we have to extract it before using it. The conventional method of doing so is smelting in the blast furnace.
Thanks to the research industry, we can use the finest types of metals made from Iron. Talking about the properties of Iron, it is a soft and ductile substance. Its melting temperature (1538 degrees Celsius) makes it a suitable metal for use in specific heated environments.
Notable Properties of Iron
● Density: 7.8 g.cm-3
● Melting Point: 1536 °C or 2800 °F
● Thermal conductivity: 76.2 W/mK
● Yield strength: 50 MPa
● Tensile ultimate strength: 540 MPa
Applications of Iron
● In the manufacture of Magnets
● In the manufacture of steel
● Used in transportation equipment
● Used in different machining process equipment
Steel
You already must be aware of Steel; it doesn’t need any introduction as already being the most common type of metal in the world.
But still, we are quite sure that you do not know some interesting facts about Steel that we are going to tell. It is an alloy of Iron in which the Carbon content is present up to 2%, but this small percentage of Carbon can significantly affect the properties of iron, making it a completely new metal “Steel.”
Steel is a ductile material, has more strength, and capability to bear more stresses and strains. Therefore it is more useful and practical to use steel in many industrial applications. Due to high heat conductivity, steel has also been a part of various kitchen cookware recently, along with other types of metals.
Steel is also used in the manufacturing of beams and structures by builders and construction engineers. It is also relatively cheaper to make as compared to other metal procurement procedures. Know about the famous Eiffel Tower? It is also made from steel, and this is the reason for its expansion up to 6 inches in summer.
Properties of Steel
● Density: 7.75 and 8.05 g/cm3
● Melting Point: 1350-1450 °C
● Thermal Conductivity: 45 W/mK
● Yield Strength: 350 MPa
● Tensile ultimate strength: 420 MPa
Applications of Steel
● Used in Gear Manufacture
● Used in building large structures (Buildings, towers, bridges, etc.)
● Used in Steel Packaging (Tin-plated)
● Used in Machining tools and weaponry.
Steel Grades by SAE (Society of Automobile Engineers)
To standardize the properties and composition of steel alloys, SAE International introduced a numbering system to categorize the alloys into specific categories. It is a four-digit steel grading system in which the first two represent the type of steel and the concentration of alloying elements, while the last two digits are meant to represent the concentration of carbon present in the metal.
The SAE Steel Grading System is beneficial for engineers and researchers for designing a particular geometry. Also, this system standardizes the material properties providing common knowledge.
Common Steel
The steel was made initially by the compounding of just Carbon and Iron, which is now known as Carbon Steel. The more Carbon we add in Iron, the harder it becomes due to properties of Carbon. However, as the hardenability increases of the metal, its elasticity decreases. Also, Steel with less carbon is easy to manufacture, handle, and recycle.
Carbon Steel is categorized into further three categories: Low Carbon, Medium Carbon, and High Carbon. Heat treatment methods commonly procure it. High carbon steel is tough and is excellent against abrasion and can resist large forces without deformations but breaks suddenly as it is brittle. On the other hand, low Carbon steel can deform a lot before failure. Carbon steel is used for everyday and cheap applications nowadays, such as building structures and simple mechanical equipment.
You can easily identify Carbon Steel because of its dull structure with a matte finish. For highly crucial areas where the corrosion and deformation cannot be tolerated at any degree, it is not recommended to use Carbon Steel due to its corrosive nature and high thermal conductivity.
Stainless Steel
It is a type of steel that has a relatively higher percentage of Chromium than other types of steel, such as 10% to 30%. The addition of excessive chromium results in excellent tolerance against corrosion and heat. Additional elements, such as nickel, molybdenum, and titanium, are also incorporated to alter the properties according to our design conditions.
Stainless Steel is a type of metal, which is needed for many applications today where the use of heat and corrosion-resistant materials is necessary due to high oxidation levels. We can see the steel in knives, kettles, and other kitchen utensils.
The rate that stainless steel corrodes is much less in comparison with other types of steel. So, using it in a harsh environment doesn’t mean that rust will never affect it. Special coatings and proper maintenance are the best way to protect any type of steel. For example, there is very limited use of stainless steel in shipbuilding. The right use of coatings, anti-corrosion systems, and frequent inspections ensure that structurally ships are safe without using stainless steel which is more expensive.
Other Alloys
Desired physical and chemical properties can be achieved by adding different types of metals on steel. These metals are added intentionally because iron and carbon alone cannot give the ductility, malleability, formability, and other physical features.
Manganese, vanadium, chromium, nickel, and tungsten are common alloy materials for steel. Every metal has a unique property. For example, tungsten gives the grain structure more stability and hardenability. Also, manganese increases the resistance to shocks and heat, making the metal suitable to use it in gear manufacture.
Some steel alloys are expensive for some projects and people use techniques like galvanization. In each task, you have to balance quality and durability with the cost.
Aluminum
Aluminum is a great alternative to steel and iron and it is one of the most essential metals in the fabrication industry. Centuries ago, aluminum was more valuable than Gold. But in the past century, Hall Heroult Process revolutionized the extraction of Aluminum from Aluminum Oxide through electrolysis and different industries were able to make use of it. Though the extraction of Aluminum is a bit pricey. So, recycling aluminum is always crucial to conserve our energy and resources.
Being extraordinarily soft and ductile, aluminum has become an ideal metal to use in fabrication techniques such as CNC machining, drilling, milling, and stamping. You can create the most complex geometries having great detail by using this metal as your source material. It’s a metal that weighs much less than steel but it has good strength. That’s why it has a much higher strength to weight ratio, making it the right choice for the automobile and aeronautics industries where overdesigning and reduced weight are significant concerns.
Like any other metal apart from benefits, aluminum has drawbacks. Some problems with aluminum have to do with its high thermal conductivity and low melting point. This makes it vulnerable to catching fire quickly. So it is always wise to clean up the surface material of Aluminum (which is Aluminum Oxide) before welding as the melting point difference will disturb the welding process. Also, the welder must be fast, as slow welding might increase the risk of burn through.
It’s not uncommon to encounter aluminum with different metals as part of the same structure. Special attention must be paid to the corrosion of aluminum with certain types of steel.
Properties of Aluminum
● Density: 2.7 g/cm³
● Melting Point: 660.3 °C
● Thermal Conductivity: 205.0 W/mK (High)
● Yield Strength: 310 MPa
● Tensile ultimate strength: 700 MPa
Applications of Aluminum
● Used in Aluminum Foils
● Kitchen Utensils
● Used in the Manufacture of window and door frames
● Used in Solar Panels
● Used as an alternative to Steel in the Automobile Industry
Copper
Copper is, arguably, one of the oldest metals used by human civilization and still a valuable metal in the fabrication industry. The alloys of copper are versatile enough to be used as a primary metal in any professional industry. This is why the world has been consuming around 18 million tonnes per annum of Copper. Another astonishing fact is that around 40% of it is recycled.
Copper has been famous for its high electrical conductivity. There are quite a few machining processes associated with copper, including stamping, forming, polishing, wire drawing, spinning, and plating. Copper is similar to aluminum in the sense that the end products are soft and must be transported and stored with exceptional care as a slight force can destroy the shape of them. This softness can also be a problem in the machining process as a slightly higher cutting force can break the edge of metal resulting in a significant loss of material.
You can apply almost every machining, joining, welding, or deforming technique to copper alloys due to their softness. One of the great benefits of using copper as a surface material is that it does not require any painting or coating because of its inherent property of resisting corrosion. In a way, the metal protects itself by forming a layer of oxides, carbonates and other molecules around it. This protective layer is called patina. The only corrosion to which copper is vulnerable is galvanic corrosion due to metal to metal contact. Arc welding, laser welding, gas-shielded welding are some of the basic welding techniques for copper.
Properties of Copper
● Density: 8.96 g/cm³ at room temperature
● Melting Point: 1,085 °C
● Thermal Conductivity: 385.0 W/mK (Very High)
● Yield Strength of Copper Alloys: 62-69 MPa
● Tensile ultimate strength: 172-220 MPa
Applications of Copper
● Transmission in Electrical Power
● Used by the Transportation Industry
● Widely used in Motors of Electrical Appliances
● Used in Plumbing Applications
● Used in Heat Exchangers (Boilers, Heaters, etc.)
Nickel
A silvery metal with a lustrous texture, nickel is a well-known element present in most of the alloys such as monel, nichrome, and permalloy. The bond process is a modern technique for the extraction of pure nickel. It has the most demand among all the types of metals in the coating industry due to its resistant nature to corrosion in water and air. Nickel is now the basic ingredient in most of the coating applications. However, this metal can be found in many alloys and the most famous of them is stainless steel.
Nickel has been continuously used in the food and electronics industries to improve the quality of the products because of its corrosion-resistant nature against various alkalis. Commonly, you wouldn’t want to use the nickel in its purest form because of its unoptimized physical and chemical properties, but an alloy of it can be very useful. Due to high thermal conductivity, nickel alloys are the best choice of material in a heat exchanger where the various fluids make it a very corrosive environment.
Nickel is easy to fabricate because it can be used in most processes. It has very good weldability due to its low work hardening rate. In simpler words, it means that bending or deformation of the material won’t make it hard and brittle.
The use of nickel is constantly increasing as there has been a constant evolution in electric and hybrid vehicles. The demand for these cars creates perfect conditions for the mass production of nickel-cadmium batteries. According to the U.S Geological Survey, around 89 million tonnes of Nickel reserves have been found in the world to date.
Properties of Nickel
● Density: 8.908 g/cm³ at room temperature
● Melting Point: 1,455 °C
● Thermal Conductivity: 90.9 – 91 W/mK (Good Conductor of Heat)
● Yield Strength: 110 MPa (Annealed)
● Tensile ultimate strength: 345 MPa (Annealed)
Applications of Nickel
● Undercoat for Chromium Plating
● Battery components require Nickel
● Used as a Catalyst for different Chemical Processes
● Used in the manufacture of Stainless Steel
● Used in the manufacture of Li-ion batteries.
Tungsten
Tungsten is a white metal that has excellent resistance against corrosion. It is famous due to its highest melting points among all the known pure metals. Most of the industries do not use tungsten in its pure form. Instead, they use it in the form of tungsten carbide, which has excellent tensile strength and hardness. It can be produced with a reaction of Tungsten and Carbon at around 1400–2000 ° C.
It is highly resistant to abrasion; this is the reason it is used in drilling and machining tool equipment easily cutting titanium and other hard materials. It is also called cemented carbide. The largest producer of tungsten in the world in China.
Tungsten Carbide is not only used in machining processes but also has a significant role in the ammo and mining industry. The researchers have found the use of it in surgical equipment such as scissors, needle holders, blade handles, etc. It’s an important ingredient for creating effective cutting tools for milling, drilling, and turning. Machining should be done with more care as we increase the tungsten amount in tungsten carbide. It is also a good idea to use coolant (of high lubricity) in the machining process. In this way, we can get extremely accurate tolerances and surface finish.
One of the most important uses of tungsten was the filament manufacture in bulbs, but it is gradually phasing out due to more energy-efficient light sources being developed. Anyway, no one can deny the significance of tungsten in the material industry as it always has extensive uses in welding and as a heating element in furnaces.
Properties of Tungsten
● Density: 19.25g/cm3
● Melting Point: 3,422 °C
● Thermal Conductivity: 173 W/mK (Good Conductor of Heat)
● Yield Strength: 750 MPa
● Tensile ultimate strength: 980 MPa
Applications of Tungsten
● Used as a heating filament
● Used in the manufacture of heavy metal alloys, e.g., HSS (High-Speed Steel)
● Used in Arc-welding electrodes
● Used by the mining and petroleum industry
● Used in the manufacture of rocket nozzles
Titanium
Titanium has recently gained popularity in the metal industry after its discovery in 1791. Being the seventh most abundant metal on Earth, Titanium is still one of the most expensive metals known to date because it is really hard to refine it into its pure form. Although it is worthwhile to extract it from its compounds and exploit its benefits.
Titanium performs great in oxidized environments because of the presence of surface oxide film. This film protects the metal in the same way patina protects copper. Depending on the thickness of the layer, the metal reflects different colors of the rainbow.
Titanium alloys provide excellent creep resistance and have relatively higher strength than other regular metals. The spring back that you will get in titanium will undoubtedly be more significant than ordinary metals due to low young’s modulus value
The hydrogen attacks on titanium much more violently than the oxygen does; therefore, the titanium must not be put in such an environment where hydrogen is present excessively. As its thermal conductivity is low, the fabricators use proper measures for its machining in the form of sharp cutting tools, and plentiful amounts of lubrication.
Properties of Titanium
● Density: 4.506 g/cm³
● Melting Point: 1,668 °C
● Thermal Conductivity: 17 W/mK (Bad Conductor of Heat)
● Yield Strength of Ti-6Al-4V (Grade 5), Annealed: 970 MPa
● Notched Tensile Strength: 1450 MPa
Applications of Titanium
● Used in Armor Plating
● Used in Missiles and Space crafts
● Used in the Automotive industry
● Used in Heat Exchanger
● Used in Desalination pipes
Lead
Although lead is one of the most widely used metals in the fabrication industry among all the types of metals, it is still rare to find in comparison to other metals on Earth. It is a bluish-white metal with a glowing look. In its pure form, it reacts with oxygen in the air to form a lead oxide on its surface, making it hard and brittle but, at the same time, it increases its resistance to corrosion.
This type of metal is very stable because very acidic solutions including hydrochloric and sulfuric acids cannot dissolve it. Due to its stability and high density, lead is an excellent material to capture or block gamma radiations. However, it is very toxic to human health if its fumes are inhaled. Decades ago it was an ingredient in many everyday items including fuel. Nowadays, the use of lead is contained.
Properties of Lead
● Density: 11.34 g/cm3
● Melting Point: 327.5 °C
● Thermal Conductivity: Very Poor
● Yield Strength: 5.5 MPa
● Ultimate Tensile Strength: 12 MPa
Applications of Lead
● Widely Used in Storage Batteries
● In the manufacture of Lead Tetraethyl
● Used in Vibration absorbers
● Used in Ammunition
● Used in Radiation Shielding
Tin
You might probably have heard of Tin Sheets. It is a usable material for the sheet metal industry because of its soft and malleable nature. It is an important element for the manufacture of different alloys that include lead. One of its common uses is to manufacture bronze.
Tin has been the industrialists’ favorite material because it is affordable in comparison with steel and copper. Also, tin is water-resistant that makes it the number one choice for food packaging. Tin plating is a common way to protect other metals by placing a layer on the surface of them. It can easily be fabricated as tin can easily be cut and shaped into different complex shapes such as diamonds, cones, or rhombus. That’s why it is used for creating jewelry, and for other home decorative purposes. Due to its durability and sustainability, it has made its place in many luxurious houses. The interior looks quite good and unique because of the tin used in walls and ceilings.
Properties of Tin
● Density: 7.287 g/cm3
● Melting Point: 231.9 °C
● Thermal Conductivity: 66.6 W/mK at 300K (Good Conductor of Heat)
● Yield Strength: 4.5 MPa at 200 °C
● Ultimate Tensile Strength: 200 MPa
Applications of Tin
● Used in Food Packaging Cans
● Used in Oil Filters
● Used in Ducts and Shelving
● Used in Toys
Zinc
Let’s talk about another interesting metal in our list of types of metals. Being the fourth widest used metal, Zinc is white-bluish metal with numerous useful properties. Whether it be the galvanization of steel or exterior applications such as roof, windows, or wall panels, zinc has common applications in every household and industry. Zinc is widely used as a corrosion-resistant material.
ZInc is an active reducing agent and moderately more reactive than most of the metals such as iron and steel. Most of today’s produced zinc is from mining, while some of its parts are recycled. You might be familiar with Brass; Zinc is a common constituent of it. It is a common catalyst for many chemical processes that need to be done on optimum conditions of temperature and reactivity.
Properties of Zinc
● Density: 7.140 g/cm3
● Melting Point: 419.5 °C
● Thermal Conductivity: 112.2 W/mK (Good Conductor of Heat)
● Ultimate Tensile Strength: 37 MPa
Applications of Zinc
● Used in the manufacture of Alloys such as Brass
● Used in Pharmaceuticals
● Used in the Textile Industries
● Used in Cosmetics
● Used in Batteries
Cobalt
Cobalt is a silver-white metal that is extremely useful. It is a very important metal for the development of batteries. Properties of this metal depend on the way that molecules are connected. There are two allotropes of Cobalt with quite different properties; the HCP structured and the FCC structured, which is ferromagnetic and can be the best fit in magnetic applications where the temperature is high. It is a moderately reactive metal and it dissolves in dilute acids. Oxygen also reacts with cobalt at high temperatures.
Like in any chemical reaction, smaller pieces of cobalt are more reactive in comparison with bigger pieces of cobalt. Cobalt is generally not explicitly mined; instead, it is gained as a by-product of iron, copper, and zinc. If you want to know about the biggest refined cobalt producer in the world, China is the answer.
Properties of Cobalt
● Density: 8.86 g/cm3
● Melting Point: 1,495 °C
● Thermal Conductivity: 100 W/mK (Good Conductor of Heat)
● Yield Tensile Strength: 100 MPa
● Ultimate Tensile Strength: 1250 MPa
Bronze
Bronze is an alloy that is made from two previous discussed metals, tin and copper. There are hundreds of applications where bronze is used widely. Bronze is a very fusible metal that makes the creation of objects with casting an easy process. However, this fact doesn’t make it soft since it is harder than copper.
In the archeological period, the hardest metal known to humans was bronze, and thus that era was called the Bronze Age. Later on, the Iron Age took over the Bronze Age, but bronze continued to be used widely. Bronze was the first alloy to be ever made, and it was made in modern-day Turkey about 5000 years ago.
Bronze is not a compound but a mixture of elements, so on paper, any proportions can be made. Bronze melts at a lower temperature than pure metal; hence is easy to sharpen and can be used in machinery and weapons.
Properties of Bronze
● Density: 8.8 g/cc
● Melting Point: 950 to 1050 °C
● Thermal Conductivity: 83.0 W/mc (Moderate Conductor of Heat)
Applications of Bronze
● Used in the making of sculptures.
● Used in the construction of tools and guns.
● Widely used in manufacturing coins.
● Widely used in musical instruments and medals.
● Due to its resistance, it is widely used in saltwater. Marine engine propellers and other parts have been developed using bronze.
● One of the uses of bronze is industrial casting because of its easy nature to work with
● Because of its non-spark nature and hardness, bronze is used in making construction tools like hammer and screwdrivers.
Brass
Brass is the last material we would like to add in our list of types of metals. It’s another alloy and it consists of copper and zinc. Proportions of zinc and copper are changed with different variations to achieve various properties. Brass is somewhat similar to Bronze; instead of tin, brass has zinc in it. Arsenic, lead, phosphorus, aluminum, manganese, and silicon can be found in brass in tiny proportions.
Lead is added into brass at around 2%, which increases the mechanical properties of brass. Brass has a very gold-like shiny appearance. However, sometimes it can be reddish gold or silver-white. The metal is commonly used and is famous for applications in low friction areas. Brass is very easy to cast, and it is a good conductor of heat.
The working capability of brass depends on the zinc contained inside it. If there is more than 45% of zinc contained in brass, then you won’t be able to work with it does not matter how hot or cold the metal is.
Applications of Brass
● Used in decoration pieces mainly because of its gold-like shiny appearance.
● Used in gears, doorknobs, ammunition, valves, and bearings.
● In Plumbing and electrical applications.
● In Musical instruments like bells and horns.
● Due to its hardness and toughness, brass has been used in marines for a long time. They were used in saltwater because of their resistance.
Final Thoughts
Hopefully, you have found value in this article. If that’s the case, sharing it would mean a lot to me. Please let me know in the comments if you want to include other types of metal.