Chemical composition
Nominal: mid-range where both limits are given, the cap where only a maximum is, balance takes the remainder. Exact specified ranges below.
| Element | Name | Content % | |
|---|---|---|---|
| Main elements7 elements | |||
| Co | Cobalt | Bal. | |
| Cr | Chromium | 20 – 24% | |
| Ni | Nickel | 20 – 24% | |
| W | Tungsten | 13 – 16% | |
| Si | Silicon | 0.2 – 0.5% | |
| C | Carbon | 0.05 – 0.15% | |
| La | Lanthanum | 0.02 – 0.12% | |
| Element | Name | Content % | |
|---|---|---|---|
| Minor & residual2 elements | |||
| Fe | Iron | ≤ 3% | |
| B | Boron | ≤ 0.015% | |
Mechanical minima by form
Guaranteed values differ by form, size and delivery condition; quotations confirm the specification, form, size and condition.
| Form | Condition | Rm MPa | Rp0.2 MPa | A ≥ % | Other requirements and notes |
|---|---|---|---|---|---|
| Bar and forgings | |||||
| Bar, forgings and flash-welded rings | Solution treated at 1177 ± 14 °C | ≥ 862 (125 ksi) | ≥ 379 (55 ksi) | ≥ 45 | Also specified: Hardness ≤ 302 HBW / 32 HRC |
| Plate, sheet and strip | |||||
| Plate, sheet and strip (over 0.51 mm) | Solution treated at 1163-1232 °C, air cooled or faster | ≥ 862 (125 ksi) | ≥ 379 (55 ksi) | ≥ 45 | |
| Sheet and strip (>0.25-0.51 mm) | Solution treated at 1163-1232 °C, air cooled or faster | ≥ 862 (125 ksi) | ≥ 379 (55 ksi) | ≥ 40 | |
| Foil and ultra-thin sheet (≤0.25 mm) | Solution treated at 1163-1232 °C, air cooled or faster | ≥ 862 (125 ksi) | ≥ 379 (55 ksi) | — | |
| Plate, sheet and strip over 0.51 mm — elevated-temperature tensile | Tested at 649 ± 3 °C, held at least 20 min | ≥ 621 (90 ksi) | ≥ 248 (36 ksi) | ≥ 50 | |
Where this grade is recommended
Matched in 3 service conditions; ranks and scores computed from the condition-scoring matrix.
| Service condition | Industry | Temperature | Rank | Score |
|---|---|---|---|---|
| Exhaust & afterburner | Aerospace | 700 – 950 °C | 1 / 8 | 93 |
| Engine hot section | Aerospace | 650 – 900 °C | 4 / 9 | 89 |
| Gas-turbine hot section | Power & Nuclear | 800 – 950 °C | 3 / 10 | 88 |
Designations & equivalents
| W.Nr. (Germany) | 2.4683 |
| EN designation | CoCr22Ni22W14 |
| Trade name(s) | Haynes 188 |
| AMS (SAE aerospace) | 5608 / 5772 / 5801 |
Cross-references are common near-equivalents for search and shortlisting; substitution across standards requires clause-by-clause verification. All grades in one cross-reference table →
Applicable standards
3 specifications. Name the standard and its edition on the order.
Guaranteed values and required tests differ between specifications — see Mechanical minima by form for the figures per form.
Frequently asked questions
What is Alloy 188 · UNS R30188?
Alloy 188 · UNS R30188 — Cobalt superalloys. Cobalt-base sheet — combustors and afterburner cans, 1100 °C class
What is the maximum service temperature of R30188?
Typically about 1100 °C; the practical limit depends on media, stress and design life — acceptance per the governing standard.
What is the tensile strength of R30188?
The specified minimum tensile strength is 862 MPa for the main product form. Minima for other forms and sizes are listed under "Mechanical minima by form" on this page.
Which standards cover R30188?
SAE AMS5608 HS188 UNS R30188, SAE AMS5772 HS188 UNS R30188, SAE AMS5801 HS188
Where is R30188 typically used?
Exhaust & afterburner (Aerospace); Engine hot section (Aerospace); Gas-turbine hot section (Power & Nuclear)
In which forms is R30188 available?
Tube, plate, strip, bar, forgings, wire and other forms — sizes and delivery condition confirmed per order, with EN 10204 3.1 / 3.2 certification.
Same series
Download PDF datasheet
This grade’s datasheet as an A4 PDF — for filing, printing or forwarding to colleagues.
Download PDF datasheetSupply & enquiry
Tube & pipeφ1 – 219 × 0.25 – 25 mm
Plate4.76 – 80 mm
Barφ8 – 300 mm
Wire & filler metalsφ0.01 – 8 mmFor this grade we can supply, against your service conditions:
- Tube, plate, strip, bar, forgings, wire and more — with size range and lead time
- Chemistry and mechanical test report (EN 10204 3.1 / 3.2)
- Like-for-like alternatives and selection advice
- Applicable standards and inspection scope
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