Senior Mechanical Engineer

At Relativity Space, we're building rockets to serve today's needs and tomorrow's breakthroughs. Our Terran R vehicle will deliver customer payloads to orbit, meeting the growing demand for launch capacity. But that's just the start. Achieving commercial success with Terran R will unlock new opportunities to advance science, exploration, and innovation, pioneering progress that reaches beyond the known.

Joining Relativity means becoming part of something where autonomy, ownership, and impact exist at every level. Here, you're not just executing tasks; you're solving problems that haven't been solved before, helping develop a rocket, a factory, and a business from the ground up. Whether you're in propulsion, manufacturing, software, avionics, or a corporate function, you'll collaborate across teams, shape decisions, and see your work come to life in record time. Relativity is a place where creativity and technical rigor go hand in hand, and your voice will help define the stories we're writing together. Now is a unique moment in time where it's early enough to leave your mark on the product, the process, and the culture, but far enough along that Terran R is tangible and picking up momentum. The most meaningful work of your career is waiting. Join us.

About the Team:

The Powder Bed Fusion Additive Manufacturing team is pushing the boundaries of what's possible in rocket propulsion hardware. Responsible for development, process, and production, the team oversees initial concept to final hardware with rigorous quality and precision. From developing print parameters on state-of-the-art 3D printers to enabling fast iteration for partner departments, the team plays a critical role in taking engine designs from concept to hot fire. The team was instrumental in producing Aeon 1 engines for Terran 1 launch and is now pioneering next-generation processes and designs for our Aeon R engines that will power Terran R. With flight hardware production scaling up rapidly, now is the time to join and make a direct impact.

About the Role:

Relativity Space is seeking a highly skilled Senior Heat Treat Process Engineer to own and optimize heat treatment processes for additively manufactured parts and welded assemblies. This hands-on role requires technical expertise in aerospace heat treatment, process development, and the ability to drive innovation in a fast-paced manufacturing environment. You'll spend significant time on the manufacturing floor working with furnaces, technicians, and cross-functional teams to establish world-class heat treatment operations for next-generation rocket components.

Key Responsibilities

• Own heat treatment processes for L-PBF additively manufactured Inconel 718 parts and welded assemblies, including development and validation of heat treatment recipes (solution annealing, aging, HIP) through material testing (hardness, tensile, microstructural evaluation)
• Drive experimentation and innovation beyond industry standards to meet production goals while maintaining aerospace quality requirements
• Author and maintain process specifications and SOPs in compliance with NADCAP and AS9100 requirements, including temperature uniformity surveys, furnace calibration records, and process validation documentation
• Lead root cause analysis for thermal processing non-conformances and develop corrective/preventive actions to prevent recurrence
• Provide training, guidance, and technical support to heat treat technicians while collaborating with materials, quality, and manufacturing teams to resolve issues and implement improvements
• Interface with suppliers and vendors for heat treatment equipment and services
• Manage equipment calibration schedules, conduct temperature uniformity surveys, and identify infrastructure needs for capital equipment improvements
• Design efficient shopfloor workflows with visual management systems to clearly identify part status and required heat treatment cycles, optimizing throughput and first-time quality

About You:

• Bachelor's degree in Materials Science Engineering, Mechanical Engineering, or Manufacturing Engineering
• 5-7+ years of heat treatment process engineering in aerospace manufacturing with proven NADCAP and AS9100 experience
• Deep understanding of heat treatment metallurgy for nickel-based superalloys (solution annealing, precipitation hardening, stress relief, HIP)
• Knowledge of aerospace heat treatment specifications (AMS2774, AMS2750) and additive manufacturing (L-PBF) heat treatment requirements
• Understanding of furnace Installation qualification, calibration, temperature uniformity surveys, and thermal processing equipment management
• Hands-on vacuum furnace operations, cycle development, and process validation
• Experience with technical writing: Specification, SOP, work instructions
• Experience training and working with manufacturing technicians

Nice to haves but not required:

• Advanced degree (MS/PhD) in Materials Science, Mechanical Engineering, or Manufacturing Engineering
• Material characterization proficiency including hardness testing, tensile testing per ASTM E8, and metallographic evaluation

At Relativity Space, we are committed to transparency and fairness in our compensation practices. Actual compensation will be determined based on experience, qualifications, and other job-related factors.

Compensation is only one part of our total rewards package. Relativity Space offers competitive salary and equity, a generous PTO and sick leave policy, parental leave, an annual learning and development stipend, and more! To see some of the benefits & perks we offer, please visit here.

Hiring Range:

$132,000-$198,000 USD

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

If you need a reasonable accommodation, please contact us at .

Please note: Relativity Space does not accept unsolicited resumes, candidate profiles, or referrals from recruitment agencies or search firms. Any unsolicited submission - via email, our website, social media, or directly to an employee - will be deemed the property of Relativity Space, and no fee will be owed absent a current, fully executed agreement with Talent Acquisition that specifically authorizes submissions for the applicable role.