High-performance / UNS R31233
Ultimet® (UNS R31233) is a cobalt-based alloy that combines excellent resistance to wear, galling and cavitation erosion with the pitting and general corrosion resistance of the best nickel alloys.
- UNS R31233
- Spec Haynes International datasheet (nominal composition)
- Density 8.47 g/cm³
Also known as / equivalents
| System | Designation |
|---|---|
| UNS | R31233 |
| Also known as | Ultimet alloy |
Chemical composition
| Element | Min % | Max % |
|---|---|---|
| Co | Bal. | — |
| Cr | — | 26 |
| Ni | — | 9 |
| Mo | — | 5 |
| Fe | — | 3 |
| W | — | 2 |
| Mn | — | 0.8 |
| Si | — | 0.3 |
| N | — | 0.08 |
| C | — | 0.06 |
Physical properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.47 g/cm³ | 0.306 lb/in³ |
| Magnetic response | Non-magnetic | — |
Available forms & specifications
| Form | Specification | Size range |
|---|---|---|
| Plates, sheets & bars | As per Haynes / purchase specification | 3 mm – 500 mm |
Corrosion & temperature resistance
Ultimet combines wear resistance with good resistance to pitting, crevice corrosion and many acids.
Applications
Ultimet®: Pump and valve parts, nozzles, mixer blades. Pump and valve components, spray nozzles, mixer blades and parts exposed to both slurry wear and corrosion.
Frequently asked questions
What is the UNS number of Ultimet®?
Ultimet® is designated UNS R31233.
What is Ultimet® used for?
Wear + corrosion resistance. Typical uses: pump and valve parts, nozzles, mixer blades.
Is Ultimet® magnetic?
Non-magnetic.
In which forms can I buy Ultimet® from Rajkamal Metals?
Coils & Strips, Sheets & Plates, Round Bars & Rods. Sizes as per standard; other sizes on request.
Do you supply a Mill Test Certificate with Ultimet®?
Yes. Actual values are given in the Mill Test Certificate (EN 10204 3.1) supplied with each order.
Last updated: 30 October 2026. Grade names identify the supply range; designations are not engineering equivalents. Availability, make, origin and documentation are confirmed at quotation.
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Need Ultimet®?
Send the grade, form, size, quantity and destination. Price on request — every offer is prepared against your specification.