Mechanical Engineer, Plasma Diagnostics

About the role

Helion is actively searching for a dedicated Mechanical Engineer to become a core member of the Science team. In this capacity, the successful candidate will be responsible for the complete mechanical lifecycle of sophisticated diagnostic instruments that are essential to plasma research and fusion energy development. You will act as a hands-on designer, taking innovative concepts from initial brainstorming sessions all the way through to robust, field-deployed hardware systems. A significant portion of this role will involve solving complex mechanical problems that arise during high-stakes experimental campaigns, requiring both creativity and rigorous analytical thinking. You will own the mechanical integrity of your designs, ensuring they meet the stringent demands of vacuum environments, thermal loads, and precise sensor alignment within the fusion device. This position provides a unique opportunity to directly contribute to cutting-edge scientific discovery by building the tools that allow researchers to measure and understand plasma behavior. The work you perform will have a direct impact on the advancement of fusion energy, translating abstract scientific goals into tangible, reliable hardware solutions.

Key facts

What you'll do

• Partner with physicists and systems engineers to dissect experimental requirements and formulate mechanical specifications for next-generation diagnostic devices.
• Drive the mechanical design process from initial concept sketches through detailed CAD models, ensuring manufacturability, serviceability, and compliance with strict engineering standards.
• Conduct in-depth structural and thermal simulations using analysis software to validate component performance under extreme operational conditions before metal is cut.
• Build, assemble, and rigorously test mechanical prototypes in laboratory settings, meticulously documenting results and iterating on designs based on empirical data.
• Investigate anomalies and failures in diagnostic hardware, performing root cause analysis to determine if issues stem from mechanical stress, thermal expansion, or integration challenges.
• Develop and maintain comprehensive technical documentation, including drawings, bills of materials, and test procedures, to ensure knowledge retention and seamless team collaboration.
• Liaise with suppliers and machine shops to guide the fabrication of custom parts, managing timelines and quality control to keep project milestones on track.
• Integrate mechanical components with electrical, optical, and vacuum systems to ensure seamless functionality within the larger experimental apparatus.
• Proactively identify opportunities to standardize components and streamline manufacturing processes to reduce costs and accelerate deployment timelines.
• Continuously expand your technical expertise by engaging with the latest research, attending internal seminars, and collaborating with subject matter experts at the forefront of plasma physics.

Requirements

• Hold a Bachelor's degree in Mechanical Engineering or a closely related technical discipline, demonstrating a foundational understanding of core engineering principles.
• Bring a minimum of 2 years of professional experience in a role that involved designing, building, or maintaining hardware for scientific or industrial applications.
• Possess practical experience with diagnostic equipment, laboratory instrumentation, or precision sensing systems that require high levels of accuracy and reliability.
• Demonstrate proven ability using CAD software such as NX or SolidWorks to create detailed part and assembly models suitable for production.
• Show familiarity with finite element analysis tools like ANSYS or FEMAP to simulate structural behavior and predict potential failure modes.
• Have hands-on experience navigating the constraints of multiple engineering domains, including mechanical design, electrical interfacing, thermal management, vacuum technology, or fluid dynamics.
• Exhibit a strong commitment to safety protocols and best practices when working with tools, machinery, and experimental setups in a technical environment.
• Thrive in a collaborative setting where clear communication of design intent and active listening to scientific feedback are essential for success.

Skills & tools

NX

SolidWorks

ANSYS

FEMAP

Practical notes

• This is an onsite role reporting to the Director of Plasma and Nuclear Science.
• Benefits include medical, dental, and vision plans for employees and families, 31 days of PTO (21 vacation, 10 sick), 10 paid holidays plus a company-wide winter break, up to 5% employer 401(k) match, short-term and long-term disability, life insurance, up to 16 weeks of paid parental leave, and an annual wellness stipend.