Helium effects and bubbles formation in irradiated Ti3SiC2

TL;DR

This study investigates how helium irradiation affects Ti3SiC2 at different temperatures, revealing that high temperatures lead to stable helium bubble formation and less structural damage, indicating good radiation resistance.

Contribution

The paper provides new insights into helium effects in Ti3SiC2 at high temperatures, showing its potential as a durable material for nuclear applications under irradiation.

Findings

High-temperature irradiation causes elongated He bubbles in nano-laminate layers.

Structural integrity of Ti3SiC2 is maintained at 750°C despite irradiation.

Irradiation-induced swelling and hardening are reduced at high temperatures.

Abstract

Ti3SiC2 is a potential structural material for nuclear reactor applications. However, He irradiation effects in this material are not well understood, especially at high temperatures. Here, we compare the effects of He irradiation in Ti3SiC2 at room temperature (RT) and at 750 {\deg}C. Irradiation at 750 {\deg}C was found to lead to extremely elongated He bubbles that are concentrated in the nano-laminate layers of Ti3SiC2, whereas the overall crystal structure of the material remained intact. In contrast, at RT, the layered structure was significantly damaged and highly disordered after irradiation. Our study reveals that at elevated temperatures, the unique structure of Ti3SiC2 can accommodate large amounts of He atoms in the nano-laminate layer, without compromising the structural stability of the material. The structure and the mechanical tests results show that the irradiation induced swelling and hardening at 750 {\deg}C are much smaller than those at RT. These results indicate that Ti3SiC2 has an excellent resistance to accumulation of radiation-induced He impurities and that it has a considerable tolerance to irradiation-induced degradation of mechanical properties at high temperatures.