Alloys are a mixture of two or more metals and elements.
Those metals and elements are often combined to increase the desired properties in the resulting alloy.
The blending of two or more metals can also bring about other unique properties that neither of the combined metals displays in its original form, making the new alloy a very useful manufacturing material for a variety of applications and products.
Businesses looking to build custom metal parts often choose alloys over pure metals because they tend to be harder, stronger, and have more anti-corrosion properties.
Choosing the right alloy can be a challenge, especially if you’re not quite sure what you are looking for.
Therefore, in this short guide, we have gone over the most common types of alloys and their uses to give you the best opportunity to find the right one for your project requirements.
Stainless steel alloys are primarily mixtures of iron and chromium.
The chromium in stainless steel (10 percent or more) forms a thin oxide layer on the surface that protects it from corrosion when exposed to oxygen.
The process of creating and forming stainless steel includes the following seven steps:
During this process, the following four grades of stainless steel are created:
While each of the four grades has distinctive properties, there are general characteristics common to all of them.
These general characteristics include:
Stainless steel is very popular in a variety of industries, the most common of which are aircraft and aerospace, oil and gas, medical equipment, and food processing.
Within these industries, stainless steel is used for the manufacturing of the following applications and parts:
Since stainless steel has a high degree of corrosion resistance, as well as heat resistance, strength, and formability, it is also a useful manufacturing material for applications within the construction and architecture industries.
Aluminum is a lightweight and flexible metal that is often combined with other elements like iron, magnesium, manganese, zinc, copper, and silicon to increase its strength, electrical conductivity and corrosion resistance.
Aluminum alloys are usually stronger and denser and have more corrosion resistance and electrical conductivity than pure aluminum. Nevertheless, they remain just as lightweight.
Aluminum alloys are created through two processes: a solid-state process and a liquid state process.
The solid-state process includes power blending, diffusion bonding, and vapor deposition.
On the other hand, the liquid state process consists of stir casting, infiltration, and finally, spray casting.
While aluminum alloys are able to maintain the original properties of aluminum after both processes have been completed, they also bring many added enhancements.
Some of these include:
All these desirable properties have made aluminum alloys the material of choice for many applications we use and come into contact with regularly, such as:
The only drawback with aluminum alloys is that they are expensive—aluminum is 20 to 30% more expensive than steel. As a result, the initial budget will play an important role when selecting them for certain applications and products.
Copper alloys are some of the most versatile metals in existence. For that reason, they are often chosen to engineer and manufacture applications that need a high degree of heat and electrical conductivity, as well as corrosion resistance.
Copper can be easily customized for a variety of uses by adding two or more different metals to it.
While there are many classifications of copper alloys, the main families include brass (copper and zinc), bronze (copper and tin), and copper-nickel.
The main process for alloying copper entails quenching a solid solution at very high temperatures and then letting it cool down at lower temperatures to solidify.
This process adds many beneficial properties to copper, including:
Even though pure copper has enough strength and ductility for applications that need to operate at high temperatures of up to 100°C (212°F), alloying it with other metals is needed for electrical applications that require heat resistance and superior electrical and thermal conductivity.
Copper alloys are also used within the automotive, plumbing, oil and gas, marine, and telecommunications industries for manufacturing the following applications:
Since copper alloys are also aesthetically pleasing due to their reddish surface, they are also used extensively for the production of musical instruments and sculpture pieces.
Iron alloys are the result of combining iron with chromium, molybdenum, titanium, selenium, manganese, silicon, and phosphorus. Doing so improves the useful properties of the metal.
Iron itself is often used as an alloying agent for many commercial alloys like cast iron and cast steel.
Iron alloys can be manufactured through five different processes:
There are a large number of iron alloy grades that can be made utilizing the above processes, including carbon steel, stainless steel, Alloy 20, and celestrium.
The common properties exhibited by all iron alloy grades include:
Iron alloys are primarily used for castings in applications within the automotive, appliance, agricultural, and machinery industries.
Iron alloy castings are often seen in the following applications:
Iron alloys are an important part of the manufacturing of steel-based composite materials as they are reasonably priced and plentiful. They also add many useful mechanical properties like high tensile strength to the basic characteristics of steel.
Gold is soft, pliable, and very expensive. However, it is way too soft for practical applications in its pure form. That is why it is combined with other metals like silver, copper, nickel, and zinc.
Gold alloys are hard, durable, and do not lose their luster when exposed to air and moisture.
Higher levels of other elements within gold alloys will cause the metal to become harder and change its color. Moreover, the cost of an alloy will be lower than that of pure gold.
It usually takes around 30 minutes to alloy gold. The process includes the following steps:
Through this process, a variety of gold alloys with different colors and karats (kt) are produced.
You can see a brief simplified demonstration of the alloying process in the video below:
As you can see, the process is based on the same principles as the industrial one. First, the gold is melted, then the other metals are added, before being put into cold water to cool before they can be manipulated further.
Here is a sampling of some of the more common gold alloys:
During the alloying process, the karats can be increased or decreased to 24 kt, 21 kt, 14 kt, and 10 kt as needed. This is done by increasing or decreasing the amount of non-gold alloying metals and elements.
While gold alloys are primarily formed to increase tensile strength and durability, they continue to maintain most of the primary properties of pure gold.
These properties include:
As you probably already know, gold alloys are mostly used for creating jewelry.
However, they can also be used for dentistry applications like crowns and bridges, as well as coins that serve as collector items or as legal tender in different countries.
Since gold and many of the other elements it is combined with are very costly, the purity levels, measured in karats, are important to estimate its end value (i.e., product value). This is especially true when it comes to valuing jewelry, coins, and ingots.
As discussed earlier, bronze is an alloy composed of copper and tin.
Bronze is made up mostly of copper and tin (12-12.5 percent) and can include lesser amounts of aluminum, zinc, nickel, and manganese.
Even though basic bronze is an alloy itself, when it is combined with more metals and non-metals like silicon, phosphorus, and arsenic, a broad range of distinct bronze alloys with varying properties are formed.
The process of creating bronze alloys is relatively simple.
First, bronze and other metals and non-metals are heated and mixed together. Second, they are combined thoroughly to form liquid bronze. Finally, they are poured into molds to cool off and take form.
While the bronze alloying process is the same for all bronze alloys, the alloys themselves are quite different in the quantity of metal and non-metal elements and the qualities they exhibit.
The different types of bronze alloys, along with their compositions, are listed below:
All of these exhibit some shared characteristics:
One of the most unique features of bronze alloys is their low-melting point (1675 F/913 C), which is much lower than that of steel or iron, making them easier to produce than either of these metals.
What is more, bronze alloys are better conductors of heat and electricity than steel and therefore more suited for applications that require such properties.
The various forms of bronze alloys were produced to display varying degrees of mechanical properties and so each one is more or less suitable for different applications in a variety of industries.
Bronze alloy applications include:
The list of bronze alloy applications is quite extensive, so we have provided only a summarized version of the most common ones for your review.
Nickel can easily be combined with many other metals and alloying elements to produce a plethora of unique properties.
Nickel is often combined with iron, copper, chromium, aluminum, titanium, and molybdenum to create applications with high corrosion and heat resistance, high-temperature strength, and shape memory.
Due to their versatility, nickel alloys have become a popular manufacturing choice for custom metal parts in many industries.
The manufacturing process for nickel alloys begins with the correct chemical composition of alloying elements and is then hot-rolled before it is formed and shaped using modern-day molding technologies.
Many types of nickel alloys can be created through this process.
These include:
All of the above nickel alloys share similar properties and characteristics to a greater or lesser extent.
These properties include:
Its ability to combine with other metals to produce a wide range of properties, especially corrosion and heat resistance, has made it very popular within the aircraft and power industries.
A comprehensive list of nickel alloy applications is given below:
As can be seen from the above properties and applications, nickel alloys have a wide reach when it comes to the manufacturing of systems and components that operate in harsh, hot, and corrosive environments.
There is no doubt that pure metals offer a wide variety of beneficial properties for businesses looking for custom metal parts for their applications. However, metal alloys offer many more added benefits to these businesses than pure metals can provide.
Metal alloys are stronger, more versatile, and more corrosion-resistant than pure metals.
That being said, choosing the right alloy for your project can be quite difficult. While the above information will help you a great deal in making the correct choice, you should still consult an expert since they have the knowledge and experience to help you make the right decision.
For further information about our alloying processes, as well as any other metal casting, forging, or plating capabilities, contact us directly via the convenient website form or request a quote here. We welcome your inquiries.
