What are Nickel Alloys?
When it comes to producing components for critical, high-stress applications, nickel alloys are a prime choice. These versatile superalloys are so resistant that they can function – and keep functioning – even in the hottest, harshest environment.
What makes a nickel alloy?
Obviously, the common ingredient in all nickel alloys is … nickel. This durable metal brings to the mix exceptional corrosion, oxidation and temperature resistance combined with a high degree of ductility and formability. It’s no wonder that nickel alloys are a stalwart choice across a range of industries and sectors. In fact, it’s estimated that year to year, 90% of all nickel sold is purchased especially to make alloys.
When it comes to creating a nickel alloy, nickel can be combined with any number of different metals, in different proportions, to produce a material with a specific set of properties. Here are some common choices, along with just some of the features they bring:
- Titanium: light-weight and high-strength, increases strength and corrosion resistance at high temperatures
- Copper: non-magnetic, with great machinability and outstanding heat and electricity conduction
- Cobalt: brings excellent corrosion resistance in extremely hot conditions
- Chromium: heightens resistance to corrosion and stress-cracking
- Aluminium: adds strength and enhances corrosion resistance
- Niobium: increases weldability and intensifies mechanical properties
There are many, many different nickel alloys, and new ones are being created or developed all the time. What unites all of them is a particular set of properties that make them especially suitable for use at very high temperatures. Let’s look at a few of these now.
Strong, ductile, resistant
Tough and versatile, nickel alloys are resistant to corrosion by a range of media, and stay impressively strong even at temperatures over 1000°C. They are usually well-suited to operating at cryogenic temperatures as well, but it’s their resistance to heat that makes them a real favourite for critical applications.
Typically, a very strong material such as iron will become brittle when worked. This means that a component made from this metal is highly likely to have a short operative life, succumbing to stress cracking in hot conditions or when subjected to repeated cyclic loading. And that means sudden – and possibly dangerous – component failure.
On the other hand, a very ductile metal such as copper is extremely easy to work and will resist embrittlement. However, it will deform very quickly in a hot environment. The component will lose its shape, again leading to sudden failure and a potentially hazardous situation.
What makes nickel alloys so special is that they are easy to work and form without becoming brittle; they also display high strength and corrosion resistance. These properties remain stable at very high temperatures and under cyclic loading, extending their operative life and making them much safer to use.
In other words, a nickel alloy combines the strength of a material such as iron – which is sometimes added in a tiny proportion to make them even stronger – with the ductility and workability of something like copper. You can expect a nickel alloy component to last 25-35 years or even longer, depending on the conditions.
Do you want to know more? Just get in touch with a member of our sales team to ask any questions or to have a chat about your needs.
