---
title: 'Principal Nuclear Materials Engineer at Helion'
canonical: 'https://feeny.ai/job/principal-nuclear-materials-engineer-helion-everett-7vvscxt7h729'
type: 'job'
last_seen: '2026-09-05'
---

# Principal Nuclear Materials Engineer at Helion

- **Company:** [Helion](https://feeny.ai/companies/helion)
- **Location:** Everett, WA
- **Compensation:** $264k–$317k
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2025-10-01
- **Last confirmed live:** 2026-09-05
- **Apply:** https://jobs.ashbyhq.com/helion/a45f7359-1915-4646-b593-4d0397d5aa6f/application

**Skills:** Radiation effects on materials, Non-aqueous corrosion, Neutron interactions, Python, MATLAB, C++, Data analysis, Statistical analysis, Technical communication, Writing

> The Principal Nuclear Materials Engineer develops designs and materials for high-radiation environments, advising engineering on radiation effects and partnering with cross-functional teams to advance Helion's fusion power mission. The role involves overseeing testing campaigns, leading strategic projects, and colla...

## Job description

## About Helion

We are a fusion power company based in Everett, WA, with the mission to build the world's first fusion power plant, enabling a future with unlimited clean electricity. Our vision is a world with clean, reliable, and affordable energy for everyone.

Since Helion's founding in 2013, we have raised $1.5 billion from long-time investors such as Sam Altman, Mithril, and Capricorn Investment Group as well as new investors including Thrive Capital, LightSpeed Venture Capital, SoftBank, and others to propel us forward. Our current prototype, Polaris, has reached record-breaking plasma temperatures of 150 million degrees Celsius (13 keV). Helion is continuing to iterate and on the path to the world's first fusion power plant, Orion.

This is a pivotal time to join Helion. You will tackle real-world challenges with a team that prizes urgency, rigor, ownership, and a commitment to delivering hard truths – values essential to achieving what no one has before. Together, we will change the future of energy, because the world can't wait.

What You Will Be Doing:

You will play a key role in developing designs and materials suited for high-radiation environments, providing analysis and guidance to engineers on the behavior and performance of a wide range of materials under radiation exposure. In this onsite role, based at our Everett, WA office, you will report to the Director of Materials Science and collaborate closely with cross-functional teams to advance Helion’s mission.

You Will:

- Advise engineering design decisions based on radiation effects (due to neutrons) on materials used within the radiation shield vault, e.g., metals used in magnet coils, dielectrics used for structure, and ceramics
- Partner with neutronics engineers to predict dpa, analyze, model, and predict macroscopic effects on material properties including thermal conductivity, electrical resistivity, and mechanical strength. Assess system-level radiation risk
- Oversee testing campaigns to quantify impact of radiation on material properties
- Lead strategic projects to expand capabilities
- Perform literature reviews on radiation effects on materials of interest and distill the information into summaries for non-nuclear engineers
- Operate in an environment with obstacles and changing requirements. Balance risks without compromising the delivery
- Partner with other internal Helion teams, external vendors, national laboratories, and universities to gather the required capabilities. Develop your network and represent Helion at technical meetings and conferences

Required Skills:

- A professional understanding of radiation effects on materials, typically demonstrated by a degree in nuclear engineering, materials science, physics, or related discipline and 15+ years of hands-on work
- 15+ years of experience handling radioactive material
- 8+ years of experience working on non-aqueous corrosion and environmentally assisted degradation mechanisms (e.g., stress corrosion cracking, creep, accelerated fatigue)
- 8+ years of experience working on neutron interactions leading to e.g., material transmutation or helium bubble generation
- 8+ years of experience performing data analysis with a common coding language (Python, MATLAB, C++), data presentation, technical communication, and writing
- Data presentation should include rigorous consideration of uncertainty and statistics

#LI-TM1 #LI-Onsite

## Benefits

Our total compensation package includes benefits, including but not limited to:

- Medical, Dental, and Vision plans for employees and their families
- 31 Days of PTO (21 vacation days and 10 sick days)
- 10 Paid holidays, plus company-wide winter break
- Up to 5% employer 401(k) match
- Short term disability, long term disability, and life insurance
- Paid parental leave and support (up to 16 weeks)
- Annual wellness stipend

Helion is an equal opportunity employer and value diversity at our company. We do not discriminate based on race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status. If you need assistance or an accommodation during the interview process, please let us know.

## About Helion

## Company Overview
- **One-liner**: Helion is building the world’s first fusion power plant to deliver clean, reliable, and affordable baseload electricity.
- **Entity Type**: Private (Series G – $465M raised in 2026 at a $15.5B post-money valuation, led by Thrive Capital)
- **Headquarters**: Everett, Washington, USA (with additional facilities in Chelan County, WA)
- **Founded**: 2013
- **Founders**: David Kirtley (CEO), Anthony Pancotti, and others

## Core Business
- **Primary industry**: Fusion energy generation (clean energy / climate tech)
- **Target customers**: B2B – utilities, large-scale energy buyers (e.g., Microsoft, Nucor), and data center operators
- **Mission**: Build the world’s first fusion power generators to provide clean, reliable, and affordable electricity for everyone.

## Products & Services
- **Polaris**: The latest prototype fusion machine – a 19‑meter device with 50 MJ capacitor banks that demonstrated deuterium‑tritium fusion in early 2026. It is a pulsed, field‑reversed configuration (FRC) reactor designed to directly convert fusion energy into electricity (no steam turbine).
- **Orion**: The planned first commercial fusion power plant, targeting 50 MW of electricity to Microsoft data centers by 2029. Modular, factory‑built generators that can be shipped to customers.
- **HERCULES Program**: A $4M initiative funding 20 research institutions to develop enabling technologies for scaled fusion deployment.

## Market Standing
- **Valuation**: $15.5 B (post‑money Series G, 2026)
- **Key Metric**: Total funding raised – $465 M (Series G) plus prior rounds (undisclosed total). Annual revenue not applicable (pre‑revenue).
- **Notable Investors/Partners**: Sam Altman (early backer, recently stepped off board), Thrive Capital (lead Series G), Microsoft (first PPA for fusion energy), Nucor (500 MW development deal)
- **Growth Signals**: ~600 employees (up from 51‑200 in earlier years); Polaris achieved first privately‑developed DT fusion demonstration; signed first ever fusion power purchase agreement (Microsoft); expanding manufacturing capacity in Washington.

## Competitive Advantages
- **Direct energy conversion**: Helion’s pulsed FRC design recovers electricity directly from the expanding plasma at >95% efficiency, skipping the inefficient steam cycle used by most fusion concepts.
- **Pulsed approach**: The reactor pulses rapidly (sub‑second), producing fusion energy in bursts that can be synchronized to the grid, and uses solid‑state switches capable of hundreds of millions of pulses.
- **Simpler magnets**: FRC plasma is self‑confining, requiring fewer and lower‑field magnets than tokamaks or stellarators, reducing cost and complexity.
- **Fuel flexibility**: Uses deuterium and tritium (with tritium breeding planned) and ultimately can burn advanced fuels (D‑D, D‑He3) as the technology matures.

## Strategic Focus
- **Commercial deployment**: Delivering 50 MW to Microsoft by 2029 (Orion plant); scaling up manufacturing to produce modular generators in factories.
- **Technology maturation**: HERCULES program to solve tritium breeding, materials, and other enabling challenges; advancing Polaris toward net electricity generation.
- **Partnership growth**: Expanding power purchase agreements and development deals with industrial and tech customers to meet surging demand (especially AI data centers).

## Why Work Here
- **Culture**: “Urgency, rigor, ownership, and hard truths” – a mission‑driven environment focused on solving the hardest problems in fusion engineering.
- **Work**: Hands‑on with real hardware (capacitors, magnets, plasma diagnostics) across mechanical, electrical, and physics disciplines.
- **Location**: Based in the Pacific Northwest (Everett & Chelan County) with immediate access to skiing, hiking, and water sports.
- **Benefits**: Premier medical/vision/dental (fully employer‑paid options), HSA contributions, wellness stipend, 5% 401(k) match, stock options, up to 12 weeks paid parental leave + 4 weeks for birthing parents, 21 vacation days, 10 sick days, 11 holidays + winter break.
- **Hybrid/Remote**: Not explicitly stated; roles appear to be on‑site in Washington (given the hardware‑focused nature).
- **Open Roles**: Engineers (mechanical, electrical, simulation, controls), magnet analysts, experimental scientists, technicians, machinists – over 100 positions listed.

## Sources
1. [helionenergy.com](https://www.helionenergy.com/) – Company overview, funding, technology, updates
2. [helionenergy.com/careers](https://www.helionenergy.com/careers) – Careers page, values, benefits
3. [helionenergy.com/careers/open-positions](https://www.helionenergy.com/careers/open-positions) – Current job listings
4. [scientificamerican.com](https://www.scientificamerican.com/article/helion-energy-is-building-a-fusion-power-plant-can-its-technology-deliver/) – In‑depth profile, 600 employees, Microsoft PPA, Polaris details
5. [indeed.com](https://www.indeed.com/cmp/Helion-Energy?campaignid=mobvjcmp&from=mobviewjob&fromjk=9e3fd74c2e72805f&tk=1jrv4ci0di9cp800) – Company size, revenue, 108 jobs

## Other roles at Helion

- [Manufacturing Engineer](https://feeny.ai/job/manufacturing-engineer-helion-everett-2151ykfwt769) — Everett, WA
- [Senior Manufacturing Engineer](https://feeny.ai/job/senior-manufacturing-engineer-helion-everett-ajdszzvj4trq) — Everett, WA
- [Manager, Electrical Engineering](https://feeny.ai/job/manager-electrical-engineering-helion-everett-xc30n5x0s4vt) — Everett, WA
- [Inventory Control Technician](https://feeny.ai/job/inventory-control-technician-helion-everett-g22e4r5tjwjb) — Everett, WA
- [Senior Production Controller](https://feeny.ai/job/senior-production-controller-helion-everett-r0kjhce1yjvs) — Everett, WA
- [Senior Mechanical Engineer, Thermal](https://feeny.ai/job/senior-mechanical-engineer-thermal-helion-everett-m44yqpk3g3z5) — Everett, WA
- [Mechanical Engineer, Fluids](https://feeny.ai/job/mechanical-engineer-fluids-helion-everett-fc4xnhqynnvh) — Everett, WA
- [Principal Applied Plasma Data Scientist](https://feeny.ai/job/principal-applied-plasma-data-scientist-helion-everett-33tnj2pdtxam) — Everett, WA
- [Senior Applied Plasma Data Scientist](https://feeny.ai/job/senior-applied-plasma-data-scientist-helion-everett-ymgakadsjxcf) — Everett, WA
- [Senior Manager, Software Engineering, Plant Control](https://feeny.ai/job/senior-manager-software-engineering-plant-control-helion-everett-sd9dj8ccv09g) — Everett, WA