3D Printing of Next-Generation Steels for Nuclear Systems 

Additive manufacturing or AM (also known as 3D printing) offers transformative potential for the nuclear energy sector, enabling rapid fabrication of complex geometries, reduced material waste, and crucially the ability to repair damaged or ageing components directly on site, significantly reducing outage time. However, the steel used in nuclear structures must perform under extreme conditions involving high temperatures, long-term mechanical loading, and intense neutron irradiation. Current AM alloys show limitations in creep resistance, microstructural stability, and defect tolerance, preventing their qualification for use in safety-critical applications.

The complexity of this challenge cannot be addressed by a single discipline or institution, and the strength of this GW4 collaboration lies in the capacity to bring together unique interdisciplinary capability across metallurgy, mechanics, irradiation effects, and computational optimisation.

The broader importance is substantial. Nuclear energy is essential to the UK’s net-zero strategy, but component ageing and long lead times hinder deployment. Novel AM steels capable of enduring creep and radiation while enabling rapid on-site repair could extend reactor lifetimes, reduce costs, and enhance safety.

Activities include:

• a workshop in Bath to align research goals and map capabilities;
• a cross-institutional sample exchange programme and pilot experiments to generate early data linking AM microstructure, creep behaviour, and radiation tolerance;
• a two-day modelling sprint hosted by Cardiff to produce AI-enhanced modelling & a digital framework, integrating experimental data into a predictive modelling environment;
• finally, a grant writing retreat and publication development event.

External partners to be approached as part of the project include UKAEA, Rolls-Royce SMR, and the Nuclear AMRC.