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Stellite 25 Round Bars Supplier in Mumbai, India – UNS R30605
Nicorex Alloys is an ISO 9001 and ISO 14001 certified supplier and stockist based in Mumbai, India. We stock and supply Stellite 25 round bars, L605 wrought bars, and cobalt alloy 25 rod products to industries across India and worldwide. We provide these round bars as classified under ASTM F90 and AMS 5759 for wrought bar products.
Stellite 25 (UNS R30605, W.Nr 2.4964) is a tungsten-strengthened cobalt-chromium alloy and the cast version of wrought alloy L605, also known as Haynes 25. The CoCrW alloy system places Stellite 25 in the same family as Stellites 1, 6, and 12, but with a composition that sets it apart in 3 ways: the lowest carbon content (0.1%), the highest tungsten (15%), and the highest nickel (~10%). Carbide content is significantly lower in the microstructure. Solid-solution strengthening from tungsten, no carbide reinforcement, gives this alloy its high-temperature capability. Tensile strength in the wrought L605 condition reaches 996–1015 MPa (144–147 ksi) with 55–60% elongation, making it a strong fabricable cobalt alloy. Hardness ranges from HRC 20 to 45, depending on work hardening.
Bars are available from 5 to 300 mm diameter and 300 to 3000 mm length in cast, wrought (AMS 5759), solution heat-treated, ground, and centreless-ground conditions. ASTM F90 covers surgical implant quality for this low-carbon cobalt alloy. Exceptional thermal fatigue resistance and hot metal-on-metal wear performance position Stellite 25 as the thermal fatigue specialist of the Stellite family. Key applications include piercing points, extrusion dies, forming tools, furnace hardware, gas turbine components, and medical implants. Nicorex Alloys also supplies Stellite alloy grade 25 plates and welding consumables.
Cobalt Alloy UNS R30605 Bar Specifications
Specifications of Stellite 25 / L605 (UNS R30605) round bar, including standards, dimensions, manufacturing, conditions, and other key details, are covered in the table below:
| Parameter | Details |
|---|---|
| Designation | Stellite 25 (cast) / L605 / Haynes 25 (wrought) |
| AMS | AMS 5759 (bar/forging), AMS 5537 (sheet), AMS 5796 (wire), AMS 5797 (rod/electrode) |
| ASTM | ASTM F90 (surgical implant) |
| Alloy System | CoCrW, solid-solution strengthened (NOT carbide-bearing) |
| Diameter | 5 mm to 300 mm |
| Length | 300 mm to 3000 mm (custom available) |
| Manufacturing | Casting (Stellite 25); Hot forging, hot rolling (L605 wrought) |
| Conditions | As-Cast, Solution Treated (1175–1230°C), Cold-Worked, Ground |
| Tolerances | Standard or h6/h7 (ground bars) |
| Certification | MTC per EN 10204 – 3.1 / 3.2 |
Chemical Composition of Stellite 25 Alloy
The chemical composition and key alloying elements of Stellite 25 Alloy are covered in the table below:
| Element | Cobalt (Co) | Chromium (Cr) | Tungsten (W) | Nickel (Ni) | Carbon (C) | Manganese (Mn) | Iron (Fe) | Silicon (Si) | Phosphorus (P) | Sulphur (S) |
|---|---|---|---|---|---|---|---|---|---|---|
| Min (%) | Balance | 19.0 | 14.0 | 9.0 | 0.05 | 1.0 | – | – | – | – |
| Max (%) | Balance | 21.0 | 16.0 | 11.0 | 0.15 | 2.0 | 3.0 | 0.40 | 0.04 | 0.03 |
Tungsten (14–16%) provides powerful solid-solution strengthening at extreme temperatures. Nickel (9–11%) stabilises the FCC structure and enables wrought processing. Carbon (0.05–0.15%) has virtually no carbide formation. Chromium (19–21%) builds a Cr₂O₃ passive layer for oxidation and sulphidation resistance.
Mechanical Properties of L605 / Stellite 25 Bar and Rod
The mechanical properties of Stellite 25 bar, like hardness, strength, elongation, and elastic modulus, are covered below. Values differ by manufacturing route:
| Property | Hardness | UTS (typical) | Yield, 0.2% (typical) | Elongation | Elastic Modulus |
|---|---|---|---|---|---|
| Value | Cast – HRC 20–45 (work hardening) Wrought – 190–240 HB |
996–1015 MPa (144–147 ksi) | 474–505 MPa (69–73 ksi) | 55–60% | ~225 GPa (32.6 Msi) |
L605 is the strongest fabricable cobalt alloy per HP Alloys, maintaining strength to 1100°C. Wrought elongation of 55–60% is dramatically higher than that of any other Stellite. Strain ageing at 370–593°C improves creep strength. Limitation: Prolonged 600–900°C exposure causes Co2W Laves phase precipitation and ductility loss.
Physical Properties of Cobalt Alloy 25
Physical properties of Stellite 25 (UNS R30605), including density, melting range, thermal expansion and conductivity, and other key properties are mentioned below:
| Property | Density | Melting Range | Thermal Expansion (20–100°C) | Thermal Conductivity (20°C) | Oxidation Resistance | Sulphidation / Carburization | Magnetic Behaviour |
|---|---|---|---|---|---|---|---|
| Value | 8.31 g/cm³ (0.300 lb/in³) | 1329–1410°C (2425–2573°F) | ~12.5 µm/m·°C | ~9.6 W/m·K | Up to 980°C (1800°F) continuous | Good up to 871°C (1600°F) | Non-magnetic (paramagnetic, austenitic FCC) |
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Available Types of Stellite Grade 25 Round Bar
Nicorex Alloys stocks Stellite 25 / L605 round bars in both cast and wrought forms:
Stellite 25 Cast Round Bar
L605 Wrought Round Bar (AMS 5759)
UNS R30605 Solution Heat-Treated Bar
Cobalt Alloy 25 Ground Bar
Stellite 25 Alloy Rod
Wear Resistance & Corrosion Behaviour of Stellite Alloy 25
Exceptional thermal fatigue resistance is the defining property. A protective oxide film forms during hot metal-on-metal contact, preventing metal transfer and adhesion damage. L605 exhibits excellent galling resistance as per HP Alloys, surpassed only by Ultimet and Stellite 6B. Work hardening during service progressively increases surface hardness. It provides good oxidation resistance up to 980°C (1800°F). Resistant to carburisation and sulphidation up to 871°C. The Cr₂O₃ passive layer protects in air and combustion gas environments. Stellite 25 retains useful strength at temperatures above 980°C and is used in applications approaching 1100°C. Creep properties improve with strain ageing for service below 704°C.
Limitations: Not recommended for low-stress or low-angle particle erosion. For abrasion, Stellites 1, 6, or 12 are superior. Not designed for corrosive aqueous media. Prolonged 600–900°C exposure causes Co2W Laves phase precipitation and ductility loss.
Industries & Applications of Stellite 25 Round Bar
Stellite 25 round bar is specified for 6 applications where thermal fatigue resistance, hot metal-on-metal wear resistance, and high-temperature strength are required:
- Piercing points for tube manufacturing and extrusion dies for hot steel. Protective oxide film prevents metal transfer during hot contact.
- L605 wrought bar (AMS 5759) for gas turbine rings, blades, and combustion chamber parts.
- Valve trim in steam and gas turbines. Furnace hardware requires sustained high-temperature strength and oxidation resistance.
- L605 bar to ASTM F90 for surgical implant applications. ISO 5832-5 covers implant-grade CoCrWNi alloy.
- Heat treatment baskets, trays, and fixtures. Resistant to carburisation and sulphidation at service temperatures.
- Resistant to hydrochloric acid, nitric acid, and wet chlorine under certain conditions. Not designed for severe aqueous corrosion.
How to Order Stellite Grade 25 Round Bar from Nicorex Alloys
Provide the following 10 documents to place an order for Stellite grade 25 round bar from Nicorex Alloys:
- Product Form — Hot Rolled / Cold Drawn / Forged Round Bar
- Size — Diameter: 6mm to 300mm — specify diameter and length
- Condition — Hot Rolled Annealed / Solution Annealed / Forged & Annealed
- Surface Finish — Black (as-rolled) / Turned & Polished / Centreless Ground
- Material Grade — Stellite 25 / Haynes 25 / L605 / UNS R30605 / W.Nr. 2.4964
- Quantity — Total weight in kg or MT (specify pieces and length)
- Standard — AMS 5537 / AMS 5759, ASTM F75, ASME Section IX
- Additional Requirements — Co-Cr-W composition confirmation, interpass temperature control, PMI, heat/lot traceability
- Documentation — MTC 3.1/3.2, PMI Report, Mechanical Properties Report, TPI Certificate
- Delivery — Domestic / International (specify destination)
Frequently Asked Questions
What is the Price of Stellite 25 Round Bar in India?
The price of Stellite 25 round bar depends on diameter, condition (cast vs wrought), and cobalt/tungsten market rates. Wrought L605 (AMS 5759) has a premium price range. Contact Nicorex Alloys for current pricing.
What is the Difference Between Stellite 25 and L605?
Stellite 25 and L605 have the same composition but different processing. Stellite 25 is cast. L605 / Haynes 25 is wrought (AMS 5759). Both share UNS R30605. Wrought L605 offers UTS ~1000 MPa and 55–60% elongation.
What is the Hardness of Cobalt 25 Alloy Round Bar?
The hardness of Cobalt 25 alloy round bar is HRC 20–45, depending on work hardening. In the annealed condition, hardness is ~250 BHN (HRB 95–105).
Can Stellite Grade 25 Be Machined?
Yes, but it work hardens rapidly. Machinability is ~12%. Use positive-rake carbide or CBN inserts. Rigid setup at no more than 75% rated capacity.
What Is the Maximum Service Temperature for Stellite Grade 25?
Stellite 25 provides oxidation resistance up to 980°C (1800°F) for continuous service. It maintains its strength up to 1100°C.
Is Stellite 25 Magnetic?
Stellite 25 is non-magnetic. FCC structure is stabilised by high nickel (9–11%) and chromium content.
What Welding Processes Work with Stellite 25?
The welding processes that work with Stellite 25 are GTAW, GMAW, SMAW, electron beam, and resistance welding. Filler used is AMS 5796 (wire), AMS 5797 (rod/electrode). No AWS ERCoCr classification exists. SAW is not recommended.
Is Stellite 25 Suitable for Abrasive Wear Applications?
No. Microstructure is free of carbide reinforcement. It is not recommended for particle erosion. For abrasion, Stellites 1, 12, or 6 are superior.