Specials
Special grades, including American alloys for specialized requirements.
Grades
Special USA Grades
Here you will find a list of the materials we can provide. If your material is not listed, please contact us.
13-8PH
20Cb3
A286
Custom 450
Custom 455
Ferralium
Greek Ascoloy
Invar 36
Invar 42
Jethete M152
Kovar
Maraging 300
Maraging 350
Nimonic 75
Nimonic 80A
Nitronic 50
Nitronic 60
Rene 41
S 32550
Stellite 6B
Tungsten
Vascojet 1000
Waspaloy
About Specials
What Are Special Alloys?
Special alloys, which we simply call specials, are materials that fall outside the common groups of carbon steel, stainless steel, and standard nickel alloys. These are often American grades known by a trade name and developed for a specific property: extreme strength, minimal expansion, wear resistance, or high-temperature strength. Metal Service Europe supplies them as forgings or machined parts, as single pieces or small series.
The list is divided into several groups. Precipitation-hardening stainless steel such as Custom 450, Custom 455, and 13-8PH combines corrosion resistance with high strength. Maraging 300 and 350 are ultra-high-strength nickel steels. Superalloys such as A286, Waspaloy, Rene 41, and Alloy 80A (Nimonic® 80A) maintain their strength at high temperatures. Invar is an iron-nickel alloy with very low expansion; Kovar also contains cobalt and expands at the same rate as certain types of glass and ceramics.
For wear and galling, there are grades such as Nitronic 60 and the cobalt alloy Stellite 6B. Many of these names are trademarks of the original producer and the property of that brand owner. We supply the brand-name material or an equivalent grade according to the same UNS, AMS, or ASTM specification, depending on what your specification allows.
Precipitation-hardening stainless steel: Custom 450, Custom 455, 13-8PH
Ultra-high-strength: Maraging 300 and 350
Heat-resistant: A286, Waspaloy, Rene 41, Alloy 80A (Nimonic® 80A), Alloy 25 (Haynes® 25)
Low expansion: Invar 36, Invar 42, and Kovar
Wear and galling: Nitronic 60 and Stellite 6B
Corrosion-resistant: 20Cb3 and super duplex S32550 (Ferralium® 255)
Applications
Applications of Specials
Valve stems, seats, and bushings that must resist galling
Bolts, shafts, and turbine parts for high temperatures
Hermetic glass and ceramic feedthroughs (Kovar)
Highly stressed shafts and tools that must remain dimensionally stable
Valve stems and wear parts that operate without lubrication
Aerospace parts in precipitation-hardening stainless steel
Molds and measurement setups with minimal thermal expansion
Our Approach
From Inquiry to Delivery
Inquiry & Specification
Specify the alloy with the corresponding specification and condition, for example, 13-8PH in H1000 or A286 according to ASTM. Also indicate if only the original brand-name material is permitted.
Specific Forging Window per Alloy
Every special alloy has its own forging window and heat treatment. We agree on the forging, solution annealing, and aging in advance for that specific alloy.
Quality Control & Delivery
Before shipping, we compare the alloy, condition, and measured values with your order. Only when everything is correct will the part be sent to you with full documentation.
Quality
Certification and Quality Assurance
Specials are often ordered according to ASTM, ASME, MIL standards, or a specific customer specification. We deliver according to those requirements and ensure that every piece is individually tested and remains traceable. If you require independent inspection, this can be performed by, for example, TÜV or Bureau Veritas. You can find more about our approach to inspection and documentation under quality assurance.
Available
Specials Available As
Depending on the alloy and the availability of the raw material, we supply specials as:
Frequently Asked Questions
Frequently Asked Questions About Special Alloys
What is maraging steel?
Maraging steel is an ultra-high-strength nickel steel with low carbon content, which gains its strength through aging: during this process, fine intermetallic particles precipitate. The number in Maraging 300 and 350 refers to the nominal yield strength level in ksi; 300 ksi is approximately 2,070 MPa. Because the steel hardly deforms during aging, it is suitable for tools, shafts, and aerospace parts that must remain dimensionally stable.
What is Invar used for?
Invar 36 is an iron-nickel alloy with 36% nickel and virtually negligible thermal expansion around room temperature. As a result, a component remains dimensionally stable during temperature fluctuations. Applications include molds for composite parts in aerospace, measuring instruments, length standards, and laser components. Invar 42 has a higher nickel content and a different expansion rate, tailored to specific applications.
What is Custom 450 and how is it indicated on a drawing?
Custom 450 is a martensitic, precipitation-hardening stainless steel from Carpenter, with UNS S45000; in ASTM A564, it is called type XM-25. According to the producer, its corrosion resistance is close to that of 304 and its strength is near that of 410. The desired strength level is set with a single aging treatment. On drawings, it is also listed as S45000 or XM-25.
What is the difference between Nitronic 50 and Nitronic 60?
Both are nitrogen-strengthened austenitic stainless steels, but with different purposes. Nitronic 60 contains extra manganese and silicon and was developed to prevent galling and wear, for example, in valve stems, seats, and bushings. Nitronic 50 emphasizes corrosion resistance combined with high strength, for example, for shafts and fasteners in seawater.
What is Stellite 6B?
Stellite 6B is a wrought cobalt-chromium-tungsten alloy, chosen for its resistance to wear and galling. Unlike Stellite 6, which is usually applied as a weld overlay, 6B is available as bar and plate according to AMS 5894. Due to low friction, this resistance remains even without lubrication. Applications include valve stems, high-temperature bearings, and bushings for pump shafts in seawater.
Are A286 and Waspaloy nickel alloys?
Not both. A286 is an iron-base superalloy with nickel and chromium, precipitation-hardenable and suitable for bolts, shafts, and turbine components at high temperatures. Waspaloy and Rene 41 are nickel-base superalloys, used for gas turbines, among other things. Alloy 25 (Haynes® 25) is actually a cobalt alloy. This distinction matters for welding, heat treatment, and when drafting the correct specification.
What is the Werkstoff number for Nimonic 80A?
Alloy 80A (Nimonic® 80A) has Werkstoff number 2.4952 and UNS N07080; 2.4631 also occurs. It is a nickel-chromium alloy that, unlike Nimonic 75, is precipitation-hardenable through titanium and aluminum. It was developed for use up to approximately 815 °C, including for turbine blades, rings, disks, and bolts. ASTM B637 is often prescribed for bars and forgings.
Do you supply brand-name material or an equivalent?
Your specification determines that. If a brand name such as Nitronic 60 or Custom 450 is on the drawing, we offer the original brand-name material or a grade that meets the same UNS, AMS, or ASTM requirements. For aerospace and defense parts, the customer often prescribes a specific producer or standard. We establish the chosen route in advance in the quotation.
How is the origin of a special demonstrated?
Every delivery of a special is accompanied by an EN 10204 certificate (3.1 or 3.2) with heat number, analysis, and mechanical values. Because specials are often chosen for one specific property, additional tests are common, such as PMI to confirm the alloy, hardness measurement, or microscopic examination. Through full traceability, every piece can be traced back to the original heat.
Why can the lead time for specials be longer?
For special alloys, the raw material is not always immediately available in every size, as demand is lower and not every dimension is kept in stock. As a result, the lead time can be longer than for common steel. In favorable cases, the requested grade in the correct diameter is quickly available from stock. We check availability immediately and provide a feasible delivery date in the quotation.
Related Grades
Grade not found?
Send us the desired grade, standard, and certification. We will quickly let you know what is possible.