Lead Nuclear Materials Engineer

About Radiant Radiant is an El Segundo, CA-based startup building the world’s first mass-produced, portable nuclear microreactors. The company’s first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases.

Radiant’s unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028.Lead Nuclear Materials Engineer Radiant is seeking a highly motivated Lead Nuclear Materials Engineer to lead Radiant’s nuclear materials team in the development, testing, and qualification of materials and related manufacturing processes used in the Kaleidos 1MWe nuclear microreactor.

The ideal candidate is excited to grow an in-house nuclear materials team, is proficient in materials selection, testing, and analysis, takes great ownership of their work end-to-end, and thrives in a highly cross-functional, fast-paced environment. Your team’s ownership spans fuel, moderators, shielding, neutron poisons, and irradiation testing. You will be a key contributor to building the world's first mass-produced, rapidly-deployable nuclear reactor.

Responsibilities & Duties Set the technical direction for the nuclear materials team, including the definition of project scopes, the guidance of day-to-day engineering and support activities, and the development of a nuclear materials roadmap to support future reactor designs and builds

Deliver materials solutions for fuel, moderator, shielding, and neutron poison designs for Kaleidos Accountable for nuclear materials engineering team’s technical output

Lead and mentor team members technically and professionally

Communicate project status, issues, and schedules to teammates and executives

Present to external stakeholders and regulatory bodies (DOE, NRC)
Review test plans, purchase orders, and analysis

Provide surge materials engineering support as-needed

Manage irradiation testing from design of experiment through irradiation to post irradiation examination (PIE)

Required Qualifications & Skills Bachelor’s degree from an accredited institution in Materials Science and Engineering, or in Mechanical, Aeronautical, Nuclear, or Chemical Engineering with a materials science and engineering focus.
5+ years of experience working in the development, testing, and/or analysis of nuclear materials for demanding load cases and environments

Hands-on experimental or testing experience in laboratory or production environments

Desired

Qualifications & Skills Master’s or PhD degree from an accredited institution in Materials Science and Engineering, or in Mechanical, Aeronautical, Nuclear, or Chemical Engineering with a materials science and engineering focus.
2+ years of engineering leadership and management experience at a company building and/or testing hardware for nuclear, aerospace, or other extreme environments

Expert-level competency in at least one area of nuclear materials such as fuel, neutron poisons, shielding, or moderators

Experience with development and qualification of material systems for use in high temperature and irradiation environments.

Knowledge of standard test methods for materials and experience with development of design allowables.

Self-motivated with strong organizational, written, and oral communication skills.

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