Source: Futurism and Engineering Materials
Summary:
An international team of researchers has developed a new type of metal alloy that could make nuclear reactors safer and more stable in the long term. The new material is said to be stronger and lasts longer than steel - the metal of choice for current nuclear reactors.
Description:
Harvesting Nuclear Power
One of the primary problems with nuclear power is that steel typically only lasts around 40 years before it weakens and becomes too defective to use. High-entropy alloys could be the solution to this current problem, as this material is stronger (and safer) than steel.
With modern-day reactors running at higher temperatures and weakening at faster and faster rates, it’s extremely important to quickly find solutions to this issue in order to prevent a nuclear disaster from happening in one of the more than 430 reactors found around the world. Nuclear power currently provides 11% of the world's electricity.
In a nuclear reactor, intense levels of heat are produced during the fission process. This process generates electricity – including a bunch of neutrons. These neutrons typically get trapped in the water inside the reactor, but some make it to the steel exterior and end up dislodging the atoms within its structure.
Nuclear reactors typically last for 40 years, because steel can become weaker or even defective over time. Modern-day reactors run at higher temperatures than ever before making the search for a new material even more urgent. If the steel exterior of the reactor becomes defective, it needs to be replaced, costing a huge amount of time and money.
Changing the Steel Exterior
According to researchers from the Oak Ridge National Laboratory in Tennessee and the University of Finland, high-entropy alloys, which use several elements in equal percentages, could be the solution.
High-entropy alloys are created with equal amounts of different metals spread out evenly across a surface. This allows each type of atom to be almost equally exposed to the bombardment of neutrons caused by the nuclear fission process within the reactor.
To test the effectiveness of these metals, scientists simulated the process inside the nuclear reactor by bombarding two alloys with nickel and gold ions. After experimentation, they were both found to have two to three times less defects than steel.
Although the idea of using high-entropy alloys in manufacturing nuclear reactors might sound like a great solution to an extremely-dangerous issue, there are some setbacks associated with it.
While high-entropy metals aren't new, it's only in recent years that scientists have managed to create them to a high enough quality to use for practical applications, and while cost remains a problem, the scientists say this should start to come down in the years ahead.
The team says these alloys won't be ready to use for a long time, but full-scale tests are planned, and there are many different metal alloy mixes that can be tested.