Special metals encompass a broad family of engineered alloys developed for performance requirements that exceed the capabilities of standard stainless steels, aluminum, or carbon steels. These materials deliver exceptional combinations of high-temperature strength, corrosion immunity, dimensional stability, shape-memory behavior, and extreme hardness — properties critical to aerospace, defense, medical, semiconductor, energy, and advanced industrial applications. Centerless Products supplies precision-ground bar, wire, and tube in the grades listed below, held to the tight tolerances your process demands.
Shape Memory Alloys
Shape memory alloys (SMAs) exhibit two unique phenomena: the shape memory effect — the ability to recover a pre-set shape upon heating above a transformation temperature — and superelasticity, where the material returns to its original form after large elastic deformations at constant temperature. Nitinol (nickel-titanium) is the dominant commercial SMA, widely used in medical guidewires, stents, and actuators. Copper-based SMAs serve cost-sensitive industrial actuator and fastener applications.
| GRADE | SPECIFICATIONS |
|---|---|
| Nitinol (NiTi 55/45) Superelastic | Bar & Wire: ASTM F2063, ISO 15841, AMS 2243 UNS N01555 — Austenitic (superelastic) condition; Af typically –10 to +10°C; guidewires, stents, orthodontic wire, actuators |
| Nitinol (NiTi) Shape Memory | Bar & Wire: ASTM F2063, ISO 15841 UNS N01555 — Martensitic (SMA) condition; Af engineered to application temperature; thermal actuators, pipe couplings, medical retrievable devices |
| Nitinol 55-Nitinol (55Ni) | Bar & Wire: ASTM F2063 Higher nickel variant for refined Af control; small-diameter wire for medical catheter and sensor applications |
| Cu-Zn-Al Copper SMA | Bar & Wire: No dominant ASTM standard; per customer specification Lower cost alternative; industrial actuators, circuit breakers, clamping devices; transformation range –100 to +200°C depending on composition |
| Cu-Al-Ni Copper SMA | Bar & Wire: Per customer specification Higher transformation temperatures than Cu-Zn-Al; high-temperature actuation applications up to ~200°C |
High-Temperature Nickel Alloys (Superalloys)
Nickel-based superalloys maintain exceptional strength, oxidation resistance, and creep resistance at temperatures above 1000°F (540°C). These alloys are indispensable in jet engine components, gas turbine hardware, high-temperature chemical processing, and nuclear applications. Many grades are precipitation-hardened through gamma-prime (γ’) or gamma-double-prime (γ”) phases to achieve tensile strengths exceeding 200 ksi at elevated temperatures.
Solid Solution Strengthened Nickel Alloys
| GRADE | SPECIFICATIONS |
|---|---|
| Nickel 200 / 201 | Bar & Wire: ASTM B160, ASTM B473, AMS 5553 UNS N02200 / N02201 — Commercially pure nickel; chemical processing, food equipment, electronics; Ni 201 (low carbon) preferred |
| Monel 400 (Alloy 400) | Bar & Wire: ASTM B164, AMS 4675, QQ-N-281 Tube: ASTM B165, ASTM B725 UNS N04400 — 67Ni-31.5Cu; seawater, hydrofluoric acid, sulfuric acid service; marine shafting, valve stems, pump shafts |
| Monel K-500 (Alloy K-500) | Bar & Wire: ASTM B865, AMS 4676, QQ-N-286 UNS N05500 — Age-hardened Monel; 3× strength of Alloy 400; propeller shafts, pump impellers, springs in seawater service |
| Inconel 600 (Alloy 600) | Bar & Wire: ASTM B166, AMS 5540, AMS 5665 Tube: ASTM B167, AMS 5580 UNS N06600 — 76Ni-15Cr-8Fe; oxidation resistance to 2000°F; heat treating equipment, nuclear engineering, chemical processing |
| Inconel 625 (Alloy 625) | Bar & Wire: ASTM B446, AMS 5666, AMS 5837 Tube: ASTM B444, AMS 5581 UNS N06625 — Outstanding fatigue and thermal fatigue strength; seawater corrosion resistance; bellows, wireline, aerospace ducts, marine |
| Hastelloy C-276 (Alloy C-276) | Bar & Wire: ASTM B574, AMS 5796 Tube: ASTM B622, AMS 5772 UNS N10276 — Widest corrosion resistance of any commercial alloy; oxidizing and reducing acids, chlorides; chemical reactors, flue gas scrubbers |
| Hastelloy C-22 (Alloy C-22) | Bar & Wire: ASTM B574, AMS 5771 Tube: ASTM B622 UNS N06022 — Superior resistance to pitting, crevice corrosion, and stress corrosion cracking vs. C-276; pharmaceutical, nuclear waste processing |
| Hastelloy X (Alloy X) | Bar & Wire: ASTM B572, AMS 5754 Tube: ASTM B622, AMS 5587 UNS N06002 — Excellent high-temperature strength and oxidation resistance; gas turbine combustion zones, industrial furnaces, petrochemical |
| Hastelloy B-3 (Alloy B-3) | Bar & Wire: ASTM B333, AMS 5756 Tube: ASTM B622 UNS N10675 — Best resistance to reducing acids (HCl, H2SO4, H3PO4); chemical process equipment, acid production |
| Incoloy 800 / 800H / 800HT | Bar & Wire: ASTM B408, AMS 5766 Tube: ASTM B407, AMS 5768 UNS N08800/N08810/N08811 — Fe-Ni-Cr; carburization and oxidation resistance; petrochemical furnace tubing, heat exchanger components |
| Incoloy 825 (Alloy 825) | Bar & Wire: ASTM B425, AMS 5829 Tube: ASTM B423 UNS N08825 — Ni-Fe-Cr-Mo-Cu; sulfuric/phosphoric acid resistance; chemical processing, pollution control, oil & gas downhole |
| Alloy 20 (Carpenter 20) | Bar & Wire: ASTM B473 Tube: ASTM B464, ASTM B468 UNS N08020 — Fe-Ni-Cr-Mo-Cu; excellent resistance to sulfuric acid; chemical process equipment, food processing, pharmaceutical |
Precipitation-Hardened Nickel Superalloys
| GRADE | SPECIFICATIONS |
|---|---|
| Inconel 718 (Alloy 718) | Bar & Wire: ASTM B637, AMS 5662, AMS 5664, AMS 5832 Tube: AMS 5589, AMS 5590 UNS N07718 — Most widely used nickel superalloy; γ'' hardened; outstanding weldability; jet engines, turbine discs, fasteners, downhole tools |
| Inconel X-750 (Alloy X-750) | Bar & Wire: ASTM B637, AMS 5542, AMS 5698, AMS 5699 UNS N07750 — γ' hardened; springs and bolting at elevated temperature; gas turbine blades, nuclear reactor components |
| Waspaloy | Bar & Wire: AMS 5544, AMS 5706, AMS 5707, AMS 5708 UNS N07001 — High-temperature strength to 1600°F; jet engine turbine discs, compressor blades, high-temperature fasteners |
| René 41 (R-41) | Bar & Wire: AMS 5712, AMS 5713, AMS 5800 UNS N07041 — Excellent strength 1200–1800°F; jet engine sheet metal, high-temperature springs, ducting |
| A-286 (Alloy A-286) | Bar & Wire: ASTM A638, AMS 5525, AMS 5726, AMS 5731, AMS 5737 Tube: AMS 5732 UNS S66286 — Fe-Ni-Cr-Ti; age-hardenable; good strength to 1300°F; jet engine fasteners, turbine wheels, blades, springs |
| Maraging 250 / 300 | Bar & Wire: AMS 6512 (250), AMS 6514 (300), ASTM A538 UNS K92890 (250) / K93120 (300) — Ultra-high strength via maraging treatment; tooling, aerospace structural, rocket motor cases |
Cobalt Alloys
Cobalt-based alloys combine outstanding wear resistance, hot hardness, and corrosion resistance with excellent biocompatibility. Wrought cobalt-chrome alloys are the dominant material for orthopedic and cardiovascular implants. Cobalt-nickel alloys like MP35N provide extremely high tensile strength for small-diameter medical wire and aerospace fasteners. High-temperature cobalt alloys retain strength and oxidation resistance in gas turbine vanes and combustion hardware.
| GRADE | SPECIFICATIONS |
|---|---|
| MP35N (Alloy MP35N) | Bar & Wire: ASTM F562, AMS 5844, ISO 5832-6 UNS R30035 — 35Co-35Ni-20Cr-10Mo; age-hardenable to 300+ ksi UTS; medical implants (bone screws, guidewires), aerospace fasteners, high-strength springs |
| L-605 (Haynes 25 / Alloy 25) | Bar & Wire: AMS 5537, AMS 5759, ASTM F90, ISO 5832-5 Tube: AMS 5796 UNS R30605 — 51Co-20Cr-15W-10Ni; excellent oxidation resistance to 1900°F; gas turbine vanes, cardiovascular implants, surgical instruments |
| CCM (Cast Cobalt) ASTM F1537 Alloy 1 | Bar & Wire: ASTM F1537, ISO 5832-12 UNS R31537 — 66Co-28Cr-6Mo; premier implant alloy; orthopedic implants, dental prosthetics, cardiovascular devices |
| CCM Plus ASTM F1537 Alloy 2 | Bar & Wire: ASTM F1537, ISO 5832-12 UNS R31538 — Higher nitrogen version of CCM; improved fatigue and tensile strength; demanding orthopedic load-bearing applications |
| Haynes 188 (Alloy 188) | Bar & Wire: AMS 5772, AMS 5608 Tube: AMS 5799 UNS R30188 — 39Co-22Ni-22Cr-14.5W; exceptional oxidation resistance and strength to 2000°F; gas turbine combustors, transition ducts |
| Elgiloy (Alloy 3J21) | Bar & Wire: AMS 5833 UNS R30003 — 40Co-20Cr-15Ni-7Mo; spring alloy; watch springs, medical guidewires, aerospace fasteners; excellent fatigue resistance |
Controlled Expansion Alloys
Controlled expansion alloys are iron-nickel (and iron-nickel-cobalt) alloys engineered to exhibit predictable, ultra-low, or matched coefficients of thermal expansion (CTE). These properties make them essential for glass-to-metal seals, precision instruments, bimetallic devices, and electronic packaging where dimensional stability across temperature cycles is critical. The family also includes high-permeability alloys used in magnetic shielding and sensor applications.
| GRADE | SPECIFICATIONS |
|---|---|
| Invar 36 (Alloy 36) | Bar & Wire: ASTM F1684, AMS 7727, NILO Alloy 36 UNS K93600 — 36Ni-64Fe; CTE ≈1.2 μin/in/°F (20–100°C); lowest expansion of common alloys; precision instruments, laser frames, LNG tank structures |
| Super Invar (Alloy 32-5) | Bar & Wire: AMS 7727 Type II UNS K93500 — 32Ni-5Co-Fe; near-zero CTE near room temperature; optical benches, precision measurement standards, satellite structures |
| Invar 42 (Alloy 42) | Bar & Wire: ASTM F30, AMS 7728 UNS K94100 — 42Ni-58Fe; CTE matched to borosilicate glass and silicon; lead frames, glass-to-metal seals, integrated circuit packages |
| Kovar (Alloy F-15) | Bar & Wire: ASTM F15, AMS 7726 UNS K94610 — 29Ni-17Co-Fe; CTE matched to hard (borosilicate) glass and alumina ceramics; transistor headers, vacuum tube seals, hermetic connectors |
| Alloy 52 (Ni-Fe 50/50) | Bar & Wire: ASTM F30 UNS K94800 — 50Ni-50Fe; CTE matched to soft (soda-lime) glass; vacuum tube envelopes, glass-to-metal seals in consumer electronics |
| HyMu 80 (High-Permeability 80) | Bar & Wire: AMS 7727, MIL-N-14411 UNS N14080 — 80Ni-Fe-Mo; extremely high magnetic permeability; magnetic shielding, transformers, inductors, fluxgate sensors |
| Alloy 49 FM (Ni-Fe 49) | Bar & Wire: ASTM F30, AMS 7728 UNS K94490 — 49Ni-Fe; CTE matched to soda-lime glass; lead wires, sealing alloys, incandescent lamp applications |
| Nichrome (Ni-Cr 80/20) | Bar & Wire: AMS 7727 / per specification UNS N06003 — 80Ni-20Cr; high electrical resistivity; heating elements, resistance wire, thermocouples; stable oxidation resistance to 1200°C |
| Chromel / Alumel (Thermocouple) | Wire: ASTM E230, ISA MC96.1 Chromel (90Ni-10Cr) / Alumel (95Ni-2Mn-2Al-1Si); Type K thermocouple pair; temperature measurement to 1260°C |
Tool Steels
Tool steels are high-carbon, high-alloy steels engineered for hardness, wear resistance, toughness, and red hardness (retention of hardness at elevated cutting temperatures). They are grouped by application and quench method: water-hardening (W), oil-hardening (O), air-hardening (A), shock-resisting (S), hot-work (H), and high-speed (M and T). Centerless Products supplies tool steel rounds in the annealed condition unless otherwise specified; all bar, wire, and tube only — no flat or plate.
Water & Oil Hardening Tool Steels
| GRADE | SPECIFICATIONS |
|---|---|
| W1 Water Hardening | Bar: ASTM A686, AMS 6455 UNS T72301 — 0.70–1.50%C; highest carbon group; simplest tool steel; small tools, drills, reamers, taps where distortion is acceptable |
| O1 Oil Hardening | Bar: ASTM A681, AMS 6435 UNS T51601 — Mn-Cr-W; excellent machinability in annealed condition; gauges, blanking dies, precision tools, knives |
| O2 Oil Hardening | Bar: ASTM A681 UNS T51602 — Higher Mn than O1; better hardenability; thread gauges, taps, reamers, broaches |
Air Hardening Tool Steels
| GRADE | SPECIFICATIONS |
|---|---|
| A2 Air Hardening | Bar: ASTM A681, AMS 6408 UNS T30102 — 5%Cr; minimal distortion on hardening; blanking and forming dies, punches, precision gauges, trimming dies |
| A6 Air Hardening | Bar: ASTM A681 UNS T30106 — Low austenitizing temperature; excellent toughness; intricate dies, precision tools requiring minimal distortion |
Shock-Resisting Tool Steels
| GRADE | SPECIFICATIONS |
|---|---|
| S2 Shock Resisting | Bar: ASTM A681 UNS T41902 — High Si; oil or water quench; pneumatic tools, chisels, rivet sets, mandrels requiring high toughness and impact resistance |
| S7 Shock Resisting | Bar: ASTM A681, AMS 6437 UNS T41907 — Air or oil quench; outstanding toughness; heavy-duty punches, dies, shear blades, plastic injection mold components |
Hot-Work Tool Steels
| GRADE | SPECIFICATIONS |
|---|---|
| H11 Hot Work (Cr) | Bar: ASTM A681, AMS 6437, AMS 6485 UNS T20811 — 5Cr-1.5Mo-0.4V; excellent toughness and thermal fatigue resistance; die casting dies, forging dies, extrusion tooling, aerospace structures |
| H13 Hot Work (Cr) | Bar: ASTM A681, AMS 6487, AMS 6488 UNS T20813 — 5Cr-1.3Mo-1V; premier hot-work grade; die casting dies, extrusion dies, forging dies, plastic injection molds |
High-Speed Tool Steels
| GRADE | SPECIFICATIONS |
|---|---|
| M2 High-Speed (Mo) | Bar & Wire: ASTM A600, AMS 6539, AMS 6541 UNS T11302 — 6Mo-6W-4Cr-2V; most widely used HSS; drills, taps, end mills, reamers, broaches, hobs |
| M7 High-Speed (Mo) | Bar: ASTM A600 UNS T11307 — High Mo-V; superior toughness vs M2; general-purpose cutting tools, drills, taps in difficult materials |
| M42 High-Speed (Co) | Bar & Wire: ASTM A600, AMS 6490 UNS T11342 — 8%Co; exceptional red hardness; cutting tools for hard, high-strength materials; aerospace alloy machining |
| M50 High-Speed (Bearing) | Bar & Wire: AMS 6490, AMS 6491 UNS T11350 — High-temperature bearing alloy as well as cutting tool; jet engine main shaft bearings, high-speed tooling |
| L6 Special Purpose | Bar: ASTM A681, AMS 6415 UNS T61206 — Ni-Mo-Cr; oil hardening; exceptional toughness for heavy-duty punches, chisels, dies, clutch parts, shear blades |
Refractory Metals
Refractory metals — defined by melting points exceeding 3600°F (2000°C) — retain meaningful mechanical properties at temperatures that would melt or severely degrade standard superalloys. This group encompasses molybdenum, tungsten, and their alloys, plus zirconium, niobium (columbium), rhenium, and tantalum. Applications span semiconductor processing, high-power electronics, X-ray targets, furnace hardware, aerospace nozzles, nuclear reactor components, and high-temperature structural elements. All supplied as precision-ground round bar, wire, or tube only.
Molybdenum & Molybdenum Alloys
| GRADE | SPECIFICATIONS |
|---|---|
| Molybdenum Commercially Pure | Bar & Wire: ASTM B387 Grade 361, AMS 7817 UNS R03600 — 99.95% Mo min; melting point 4753°F (2623°C); furnace heating elements, sputtering targets, electrodes, missile nozzles, TFT substrates |
| TZM (Mo-0.5Ti-0.1Zr) | Bar & Wire: ASTM B387 Grade 364, AMS 7817 Type 2 UNS R03640 — Titanium-zirconium strengthened; 2× creep strength of pure Mo; hot-work tooling, piercing mandrels, glass-melting electrodes, rocket nozzles |
| Mo-30W (Molybdenum-Tungsten) | Bar: ASTM B387 Grade 365 UNS R03650 — 70Mo-30W; improved corrosion resistance to molten zinc; zinc die casting components, continuous galvanizing hardware |
| MoRe 41 (Mo-41Re) | Bar & Wire: Per specification (AMS / ASTM not yet standardized) 41% Rhenium addition dramatically improves ductility and workability; thin-wall tubing, fine wire, aerospace gimbal bearings, high-reliability electronics |
| MoRe 47.5 (Mo-47.5Re) | Bar & Wire: Per specification Near-sigma phase composition; maximum ductility for Mo-Re system; welding wire for refractory assemblies, extreme-environment sensors |
Tungsten & Tungsten Alloys
| GRADE | SPECIFICATIONS |
|---|---|
| Tungsten Commercially Pure | Bar & Wire: ASTM B760, AMS 7897 UNS R07004 — 99.95% W min; melting point 6192°F (3422°C); highest melting point of all metals; X-ray targets, filaments, electrodes, radiation shielding |
| W-3Re (Tungsten-3% Rhenium) | Bar & Wire: ASTM B760, AMS 7897 Type 2 3% Re improves ductility and workability; thermocouple wire (W-3Re / W-25Re Type D pair), high-temperature furnace elements |
| W-25Re (Tungsten-25% Rhenium) | Bar & Wire: ASTM B760, AMS 7897 Type 3 25% Re; significantly improved room-temperature ductility; thermocouple wire (Type D), aerospace nozzle throats, plasma spray components |
| WC-Ni / WHA (Tungsten Heavy Alloy) | Bar: ASTM B777 Class 1–4 UNS R07001 — 90–97W balanced with Ni and Fe or Ni-Cu; density 16.9–18.5 g/cc; kinetic energy penetrators, radiation shielding, balancing weights, vibration dampers |
Zirconium
| GRADE | SPECIFICATIONS |
|---|---|
| Zirconium 702 (Reactor Grade) | Bar & Wire: ASTM B550, ASTM B351, AMS 4850 Tube: ASTM B523 UNS R60702 — Commercially pure; outstanding corrosion resistance in HCl, H2SO4, and NaOH; nuclear reactor cladding, chemical processing equipment |
| Zirconium 705 (Zr-2.5Nb) | Bar & Wire: ASTM B550, ASTM B351 Tube: ASTM B523 UNS R60705 — 2.5% Nb addition for higher strength; chemical process piping, valves, pump shafts in highly corrosive service |
| Zircaloy-2 / Zircaloy-4 | Bar, Wire & Tube: ASTM B353, ASTM B811 UNS R60802 / R60804 — Nuclear reactor fuel cladding; low neutron absorption cross-section; thermal and fast reactor applications |
Niobium (Columbium)
| GRADE | SPECIFICATIONS |
|---|---|
| Niobium C-103 (Nb-10Hf-1Ti) | Bar & Wire: AMS 7856, AMS 7857 UNS R04210 — Melting point 4474°F; rocket nozzles, thrust chambers, spacecraft propulsion; excellent oxidation resistance when coated |
| Niobium C-129Y (Nb-10W-10Hf-0.1Y) | Bar & Wire: Per specification Higher strength refractory niobium alloy; advanced aerospace propulsion, hypersonic leading edges |
| Niobium Commercially Pure | Bar & Wire: ASTM B392, ASTM B393 Tube: ASTM B394 UNS R04200 — Superconducting at 9.3K; MRI accelerator magnets, superconducting RF cavities, sodium vapor lamp electrodes, chemical processing |
Rhenium
| GRADE | SPECIFICATIONS |
|---|---|
| Rhenium Commercially Pure | Bar & Wire: Per specification (ASTM B708 — sheet; bar per customer spec) UNS R04700 — Melting point 5767°F (3186°C); second highest of all metals; mass spectrometer filaments, ion thruster grids, X-ray targets, thermocouples |
| Re-W Alloys (see MoRe above) | Wire: Per specification (W-3Re, W-25Re listed under Tungsten) Rhenium additions improve ductility of both tungsten and molybdenum; thermocouple wire (Types C, D), high-reliability aerospace wiring |
Tantalum
| GRADE | SPECIFICATIONS |
|---|---|
| Tantalum Commercially Pure | Bar & Wire: ASTM B365, AMS 7847 Tube: ASTM B521 UNS R05200 — 99.9% Ta; melting point 5463°F; inert in nearly all acids except HF and fuming H2SO4; chemical process equipment, capacitor wire, bone-repair implants, surgical sutures |
| Ta-10W (Tantalum-10% Tungsten) | Bar & Wire: ASTM B365 Grade R05255 Tube: ASTM B521 UNS R05255 — Improved strength vs. pure Ta; rocket nozzles, corrosion-resistant springs, high-temperature structural components |
Your Partner for Critical Applications — Precision Grinding with Consistent Results
Our centerless grinding capabilities ensure your special metal components meet the tightest dimensional tolerances and surface finish requirements — whether the challenge is maintaining ±0.00004″ (2μm) diameter on a Nitinol guidewire blank, holding concentricity on a TZM electrode, or achieving a 4μin Ra finish on a cobalt-chrome implant bar. We supply bar, wire, and tube only; no plate or flat material.
Whether you are producing jet engine hardware, medical implants, semiconductor process equipment, or defense components, Centerless Products delivers the material consistency and dimensional accuracy your manufacturing process demands. Contact us today to discuss your needs.