What is an Alloy?

An alloy is a combination of a metal with at least one other metal or nonmetal. The combination must be part of a solid solution, a compound, or a mixture with another metal or nonmetal for it to be considered an alloy. The most common way to combine metals into an alloy is by melting them, mixing them, and then allowing them to solidify and cool back to room temperature. This process enhances the properties of the original metal, such as its strength, durability, corrosion resistance, or electrical conductivity. By altering the mixture’s components and proportions, manufacturers can create alloys with specific characteristics tailored to various applications, from construction materials and automotive parts to electronics and aerospace components. This ability to customize the physical and chemical properties of metals through alloying is a cornerstone of materials science and engineering, leading to innovations in technology and manufacturing.

Why are Alloys Used?

Metal alloys are used because they typically have enhanced mechanical or chemical properties. Alloying elements can be added to a metal to increase several properties, including hardness, strength, corrosion resistance, machinability, and much more. These improvements make alloys indispensable in various applications across multiple industries. For instance, adding carbon to iron creates steel, an alloy with significantly greater strength and durability than pure iron, making it a cornerstone material in construction and manufacturing. Similarly, the creation of aluminum alloys by adding elements like copper, magnesium, or silicon results in materials that are both lightweight and strong, ideal for use in the automotive and aerospace industries.

The use of alloys allows engineers and designers to tailor materials to meet the specific demands of their applications, from the extreme temperatures and pressures found in jet engines to the corrosive environments of marine hardware. This versatility extends to everyday objects like electronics, sporting goods, and coins, demonstrating the extensive role alloys play in modern society. By combining different metals and nonmetals, we can create materials that offer superior performance, longevity, and cost-effectiveness compared to their pure-metal counterparts.

Where are Alloys Used?

Alloy metals find applications across a vast array of fields due to their enhanced properties over pure metals. These applications capitalize on the improved strength, corrosion resistance, electrical conductivity, and other specialized characteristics of alloys.

Construction and Infrastructure – Steel alloys are utilized in the construction of buildings, bridges, and infrastructure due to their high strength and durability. Stainless steel, an alloy of iron, chromium, and sometimes nickel, is used for its corrosion resistance, making it ideal for architectural facades, handrails, and outdoor structures. Reinforced concrete incorporates steel rebar (an alloy) for strength and resilience.

Automotive and Aerospace – Aluminum alloys are widely used in the automotive and aerospace industries for their high strength-to-weight ratio. Alloys like 6061 are used to manufacture aircraft structures, automotive frames, and wheel rims because of their excellent fatigue resistance and weldability. Titanium alloys are employed in aircraft engines and frames for their high strength, light weight, and resistance to high temperatures.

Electronics – Due to their excellent electrical conductivity, copper alloys are essential in electrical wiring and components. Brass, an alloy of copper and zinc, is used in electrical connectors and fittings. Solder, an alloy typically made from tin and lead (though lead-free versions exist), is used to join electrical components.

Medical Devices – Stainless steel and titanium alloys are used in medical implants and surgical instruments for their biocompatibility, strength, and corrosion resistance.

Energy – Nickel, cobalt, and iron-based alloys are critical in the energy sector, particularly in constructing turbines for power plants due to their ability to withstand high temperatures and corrosive environments.

Consumer Goods – Gold and silver alloys are preferred in jewelry and watches for their improved hardness and durability. White gold, an alloy of gold with nickel or palladium, is popular for its platinum-like appearance.

Marine Applications – Bronze and brass alloys are commonly used in marine hardware, including propellers and fittings, due to their resistance to saltwater corrosion.

Tool and Die Making – Tool steels, which are alloys designed for high hardness and resistance to abrasion and deformation, are used to manufacture cutting tools, dies, and moulds.

What are Common Alloys?

Alloys are so abundant throughout the metalworking industry that there are too many to list – in fact, it is far less likely to work with a non-alloy or “pure metal.” Even low carbon mild steel – perhaps the most frequently used material in metal fabrication – is an alloy of iron and carbon. An example of a steel alloy would be AISI 1018. Cast iron is another alloy of iron and carbon, with even higher amounts of carbon than mild steel.

Aluminum is often alloyed with other elements, giving it the attributes required for the desired application. For example, aluminum 6061 and 2024 have high additions of manganese or copper, respectively.

Alloys can be highly complex. Austenitic stainless steels, such as Grade 316, are a synthesis of iron, chromium, nickel, and some other metals and nonmetals. Bronze (an alloy of copper and tin) is often further alloyed with elements such as aluminum. Grade C954 is an example of an aluminum bronze alloy.

Tool steels like D2 are mostly made of iron but have many different additions of other metals and nonmetals, such as chromium, vanadium, manganese, silicon, and carbon, depending on the desired mechanical properties.

What are Some Common Alloying Elements?

There are a wide variety of alloying elements that serve different purposes for different base materials:

  • Chromium is a metal frequently used to help alloys resist corrosion. Depending on the material, it can also increase hardness and strength.
  • Nickel is a metal often added to materials to increase toughness. Austenitic stainless steels have high addition levels of nickel, which also acts as an austenite promoter.
  • Copper is a metal used to make materials like aluminum precipitation-hardenable. In steel, copper can increase corrosion resistance but can decrease the corrosion resistance of aluminum.
  • Manganese is a metal usually alloyed to improve strength. Manganese alone as an alloying element is not affected very much by heat treatment, making it suitable for higher temperature applications.
  • Tungsten is a metal alloying element used to improve wear resistance (especially at high temperatures), toughness, and strength.
  • Lead is a metal alloying element that is used to improve machinability.
  • Silicon is a nonmetal alloying element. It is often used as a deoxidizer in metals. Silicon also increases strength and can reduce melting temperature.
  • Carbon is a nonmetal alloying element that is used to manufacture steel. Carbon additions are often used in steel and cast iron alloys to increase strength and hardness.

Want to learn more about common alloying elements? Check out Part 1 and Part 2 of our “Common Alloying Elements” series.

What is an Alloy? Find Out More at Metal Supermarkets

Alloy metals represent a fundamental pillar in the world of materials science and engineering, offering a versatile and powerful means to enhance and tailor the properties of metals to meet the demands of modern applications. By combining different metals and sometimes nonmetals, we can create materials that are stronger, more durable, more corrosion-resistant, or more conductive than their component elements alone. This ability to customize and improve upon the natural properties of metals has been a key driver of technological advancement and industrial growth.

From the towering structures of our cities to the devices in our pockets, the cars we drive, and the planes that traverse our skies, alloys are integral to the fabric of our daily lives. Their development and use signify human ingenuity’s ability to innovate and adapt materials for an ever-expanding array of applications.

For those looking to explore alloys further, whether for a project, repair, or innovation, Metal Supermarkets offers an unparalleled selection of alloy metals. With a vast inventory ranging from aluminum to stainless steel, bronze to brass, and everything in between, we are your one-stop shop for all your metal needs. Shop online or check out your closest store to find the perfect alloy metal for your next project.

Metal Supermarkets

Metal Supermarkets is the world’s largest small-quantity metal supplier with over 125 brick-and-mortar stores across the US, Canada, and United Kingdom. We are metal experts and have been providing quality customer service and products since 1985.

At Metal Supermarkets, we supply a wide range of metals for a variety of applications. Our stock includes: mild steel, stainless steel, aluminum, tool steel, alloy steel, brass, bronze and copper.

We stock a wide range of shapes including: bars, tubes, sheets, plates and more. And we can cut metal to your exact specifications.

Visit one of our 125+ locations across North America today.

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