Gold slows down the growth of helium bubble in iron

TL;DR

This paper uses first-principles calculations to show that gold (Au) can slow helium bubble growth in iron by forming a barrier layer at the bubble surface, which could impact material durability.

Contribution

It introduces a novel mechanism where gold segregation at helium bubbles in iron acts as a barrier, reducing bubble growth, based on first-principles computational predictions.

Findings

Au has a strong affinity to He in bcc Fe.

Au-Au bonding at the bubble surface is stronger than Fe-Fe and Au-Fe bonds.

Gold segregation slows helium bubble growth in iron.

Abstract

We predict by first-principles calculations that Au have strong affinity to He in bcc Fe. The Au-Au bonding in the segregated Au layer at the He bubble surface is stronger than Fe-Fe and Au-Fe interactions; therefore this layer becomes an effective barrier to further He and slows down the bubble growth.