Material selection is one of the most important decisions when it comes to the success of space missions. For engineers, material scientists, procurement managers, and program managers, understanding the range of materials and specific requirements of the industry is essential. Read on to learn about the demands of the space industry, primary metals for space applications, and the non-negotiables when it comes to selecting your metal suppler.
Why Space is More Demanding Than Commercial Aerospace
When it comes to material requirements for space applications, the requirements are much more demanding than commercial aerospace. While both spacecrafts and commercial aerospacecrafts both operate in extreme conditions, the conditions of space are fundamentally more severe and less forgiving than commercial aviation.
Metals for space applications must be able to tolerate:
- Temperature cycling from –250°F to over 1,000°F
- Radiation exposure
- Extreme vibration and acoustic loads
- Vacuum environments
- Strict weight requirements
While commercial spacecrafts spend at most a day in the air, once spacecrafts have left earth, they may not return for years at a time. In almost all cases, repairs can’t be completed in space, so reliable materials are imperative. When selecting aircraft materials, it’s important to look for the following characteristics:
- Fatigue strength
- Corrosion resistance
- Thermal expansion stability
- Radiation tolerance
- Long-term dimensional stability
Primary Metals for Space Applications
The space industry relies on a number of high-performance materials that perform reliably in extreme requirements. Read on to learn the primary metals in commercial aerospace applications.
Aluminium Alloys
Aluminum alloys are among the most widely used materials in spacecraft due to their excellent strength-to-weight ratio and machinability.
Key properties of aluminium alloys include:
- Good strength-to-weight ratio
- Good fatigue resistance
- Strong thermal conductivity
These alloys are often used in:
- Structural frames for satellites
- Instrument housing
- Cryogenic tank structures
- Secondary launch vehicle structures
Common grades of aluminium alloys in the space industry include:
- 6061 aluminium: High corrosion resistance, good strength, and good machinabilityÂ
- 7075 aluminium: Excellent fatigue resistance and high strength-to-weight ratio
- 2024 aluminium: High strength-to-weight ratio and fatigue resistanceÂ
Stainless Steel
Stainless steel is heavier than aluminum, but it excels in applications where strength, toughness, and temperature resistance is required.
The key properties of stainless steel that make it beneficial in the space industry include:
- High strength and toughness
- Corrosion resistance
- Cryogenic capabilities
- Good weldability
Stainless steel alloys are generally used for:
- Propellant tanks
- Structural supports
- Fluid system components
- Ground support hardware
Common grades of stainless steel in the space industry include:
- 304 stainless: Excellent corrosion resistance and formabilityÂ
- 316 stainless: Superior corrosion resistanceÂ
- 321 stainless: High temperature resistance
Nickel Alloys
Nickel superalloy materials for spacecraft are essential for propulsion and high temperature exposure. It excels when conventional steels can’t maintain their strength.
Key properties of nickel superalloys for spacecrafts include:
- Excellent strength in high temperatures
- Good oxidation resistance
- Excellent creep resistance
- Remains stable throughout thermal cycling
Typical applications for nickel alloys include:
- Rocket engine components
- Turbopump assemblies
- Exhaust structures
- High-temperature fasteners
Common nickel alloys for space include:
- Iconocel 718: High strength and corrosion resistance in cryogenic temperaturesÂ
- Iconocel 625: High-temperature strength, corrosion resistance, and ductilityÂ
Titanium Alloys
Titanium provides a combination of excellent strength-to-weight ratio and corrosion resistance. They can be up to 45% lighter than steel and many times stronger than aluminium alloys.
Key properties of titanium alloys include:
- Exceptional strength-to-weight ratio
- High corrosion resistance
- Excellent fatigue resistance
Titanium aircraft alloy materials are typically used in:
- Load-bearing structural components
- Fasteners
- Pressure vessels
- Propulsion system hardware
Common types of titanium space-grade alloys include:
- Grade 5: High strength and toughness and good weldability
- Grade 23: Good toughness and ductility at cryogenic temperatures
Non-Negotiables for Metals for Space Applications
The high-stakes nature of space programs means compliance standards, traceability, and quality assurance are non-negotiable. This is necessary for risk management and program success.
In order to meet traceability standards, manufacturers must provide:
- Mill test reports
- Heat lot identification
- Certification documentation
- Inspection data
It’s also essential to find an AS9100 certified metal supplier. This QM standard ensures that suppliers maintain quality management systems that are specifically designed for aerospace and space. Working with a certified supplier reduces your risk.
Fry Steel: Your Space Program Specialty Metal Supplier
At Fry Steel, we support the space and aerospace with specialty metals that meet the industry’s demanding requirements. We maintain ISO 9001, AS9100D, and AS9120B certifications and provide full material traceability for all of our products.
Our extensive supply includes a wide range of specialty bar products from 1/16th inch to 24 inches in diameter. With decades of experience supporting mission-critical industries, we understand the demanding requirements space requires. Find a Fry Steel rep in your area today.
