Mechanical Engineer; Nuclear​/Reactor Systems) Remote

Mechanical Engineer (Nuclear / Reactor Systems)

Remote, USA

Applied Atomics delivers firm, clean electricity with proven technology. We design, build, and operate nuclear plants directly alongside the facilities they power. With n o reactor science or new fuel to invent , we have n o reason to stall. We are the first fully integrated nuclear power provider built to deploy now. Founded by a team of engineers and operators who built the launch sites, test complexes, and factories behind SpaceX , designed and commercialized nuclear reactors, and ran billion-dollar asset portfolios , the team is now focused on clean power deployment.

Applied Atomics is b acked by Alpaca VC, Transition, and Morpheus Ventures.

About the role:

Applied Atomics is seeking a Mechanical Engineer to design, develop, and develop the high-reliability mechanical systems that support our reactor product.

You will work on hardware such as precision motion systems, actuation mechanisms, structural components, safety-related assemblies, and complex mechanical interfaces within the reactor and adjacent systems. This role blends mechanical engineering fundamentals with the unique environmental and reliability needs of a nuclear system. Prior nuclear experience is not required; we are looking for strong mechanical engineers who can design robust hardware, solve complex problems, and iterate rapidly alongside world-class nuclear engineers.

This role is ideal for someone who wants broad responsibility,thrives in a fast-pacedhardwareenvironment, and wants tomake a lasting impact on the design of afirst-of-a-kind (FOAK) nuclear power system.

Why we need you

We are transitioning nuclear energy from a theoretical science into a practical reality, and that requires practical problem-solvers. We need engineers who are eager to take direct responsibility for their work and see it through to completion. Your role will be critical in transforming complex designs into safe, reliable, and operational power plants that will operate for decades to come.

What you will do

Mechanical System Design

• Design and develop mechanical systems and components for the reactor environment, including motion systems, actuators, linkages, structural components, and safety-related mechanical assemblies.
• Support the development of hardware used in reactivity control, mechanical actuation, and system-level motion interfaces.
• Conduct design trade studies, concept development, and material selection.
• Perform structural and thermal analysis using hand calculations and finite element analysis tools (ANSYS, Abaqus, Nastran, etc.)
• Conduct tolerance stack-ups, GD&T applications, and precision mechanical alignment studies.
• Evaluate fatigue, wear, friction, vibration, and reliability performance.
• Create manufacturing, assembly, and integration instructions.
• Develop and execute test plans for components and assemblies.
• Support hardware bring-up, test execution, failure analysis, and design iteration.
• Identify and work with suppliers for machined parts, actuators, bearings, materials, and assemblies.
• Ensure components meet dimensional, functional, and reliability requirements.

Cross-Functional Collaboration

• Work closely with nuclear engineers, thermal-fluids engineers, materials engineers, and systems engineering.
• Ensure mechanical designs align with nuclear safety, reliability, and performance requirements.
• Contribute to system-level integration across reactor subsystems.

Additional Responsibilities

• Take end-to-end responsibility for your projects, from initial concepts through to deployment and ongoing operations
• Partner closely with our multidisciplinary team of experienced engineers to tackle complex, cross-functional…