Precious Metal Pt90Rh10 TC-Class1
Certified grade
ASTM E230 Type S · EN PtRh10
TC-Class1 = type S thermocouple wire, IEC 60584-1 Class 1 / ASTM E230 special limits
Annealed, EMF-calibrated wire pairs supplied with certificate when tolerance of ±1 °C / ±0.25 % is required for reference thermometry.
Values for the TC-Class1 condition
Other Pt90Rh10 tempers and conditions
Pt90Rh10 is listed in 6 conditions; see the grade overview at Pt90Rh10.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
induction-melted crucibles, bushings, labware | Use for melt-formed vessels and thick shapes; coarse grain gives lower strength and worse high-temperature creep than wrought/ZGS material. | 150 | 280 | 25 | 83 HB | 8.9 % IACS |
AnnealedDefault soft, fully recrystallized wire/sheet (thermocouple grade) | Standard stocked condition for S-type thermocouple wire and lab foil: maximum ductility and stable, calibration-conforming EMF. | 170 | 320 | 35 | 88 HB | 9.1 % IACS |
TC-Class1This page Type S thermocouple wire, IEC 60584-1 Class 1 / ASTM E230 special limits | Annealed, EMF-calibrated wire pairs supplied with certificate when tolerance of ±1 °C / ±0.25 % is required for reference thermometry. | 170 | 320 | 35 | 88 HB | 9.1 % IACS |
ZGS / DPH oxide-dispersion-strengthened PtRh10 | Zirconia-grain-stabilized version for glass-fibre bushings and high-temperature vessels needing greatly improved creep life and grain stability above 1200 °C. | 220 | 350 | 20 | 107 HB | 9 % IACS |
Half hard | Choose when the wire or strip must hold its shape (formed leads, spring contacts) yet still take a bend. | 400 | 500 | 10 | 152 HB | 8.9 % IACS |
Hard drawn | Highest room-temperature strength/stiffness for fine wire handling, springs and electrodes; anneal (or first heat cycle) before use as a calibrated thermocouple. | 620 | 720 | 3 | 19 HRC | 8.8 % IACS |
What is Pt90Rh10 TC-Class1?
Pt90Rh10 TC-Class1 is Pt90Rh10 in a TC-Class1 certified grade — annealed, EMF-calibrated wire pairs supplied with certificate when tolerance of ±1 °C / ±0.25 % is required for reference thermometry. Pt90Rh10 TC-Class1 has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 320 MPa (46.4 ksi) — weaker than 64% of precious metal grades. Elongation at break is 35% and the elastic modulus is 193 GPa (28 Msi). Pt90Rh10 TC-Class1 has a density of 19.97 g/cm³ (0.721 lb/in³), heavier than 92% of precious metal grades. It melts at 1,850°C (3,362 °F). Annealed is the default condition FabDigit quotes; TC-Class1 is available on request or by drawing note.
Advantages
- High service temperature — 1,450°C (2,642 °F), better than 99% of precious metal grades
- Stiff — 193 GPa (28 Msi), better than 95% of precious metal grades
- Good corrosion resistance — 99/100, better than 93% of precious metal grades
- Ductile — tolerates forming and impact — 35%, better than 83% of precious metal grades
- Readily welded — 75/100, better than 78% of precious metal grades
Limitations
- Poor heat conductor — 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 94% of precious metal grades
- Difficult to machine — 25/100, worse than 94% of precious metal grades
- Heavy — 19.97 g/cm³ (0.721 lb/in³), worse than 92% of precious metal grades
- High embodied carbon — 14,000 kg CO₂/kg, worse than 88% of precious metal grades
- Low electrical conductivity — 9.1 % IACS, worse than 82% of precious metal grades
Pt90Rh10 TC-Class1 properties
Typical room-temperature values for Pt90Rh10 TC-Class1; 19 are specific to this condition. Other listed values are Pt90Rh10 reference data and may not represent this condition. Bars are the position among precious metal grades.
Physical3
Pt90Rh10 TC-Class1 has a density of 19.97 g/cm³ (0.721 lb/in³), heavier than 92% of precious metal grades. It melts at 1,850°C (3,362 °F).
Mechanical10
Pt90Rh10 TC-Class1 has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 320 MPa (46.4 ksi) — weaker than 64% of precious metal grades. Elongation at break is 35% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
Pt90Rh10 TC-Class1 is rated for continuous service to 1,450°C (2,642 °F). It conducts heat at 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 94% of precious metal grades. Thermal expansion is 9 µm/m·K (5 µin/in·°F).
Electrical3
Pt90Rh10 TC-Class1 conducts electricity at 9.1 % IACS, worse than 82% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (99/100), better than 93% of precious metal grades.
Sustainability3
Producing a kilogram of Pt90Rh10 TC-Class1 takes about 200,000 MJ of energy and emits 14,000 kg of CO₂ — more than 85% of precious metal grades. Typical recycled content is 50%.
Manufacturability8
Pt90Rh10 TC-Class1's machinability is poor (25/100, worse than 94% of precious metal grades); weldability very good (75/100); formability excellent (88/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Pt90Rh10 TC-Class1
Is Pt90Rh10 easy to machine?
Very gummy and expensive — use sharp carbide/diamond tools, light DOC, flood coolant, and capture every chip for refining; wherever possible form from wire/foil instead of cutting.
Can Pt90Rh10 be welded?
Junctions are made by resistance, microplasma, laser or oxy-hydrogen fusion welding without flux; keep the joint free of Si, Fe and Pb contamination to avoid embrittlement and EMF drift.
Can Pt90Rh10 be formed, bent or molded?
Excellent cold formability in the annealed state (drawn below 0.05 mm, rolled to foil); interstage anneal at 900–1100 °C in air, and re-anneal thermocouple wire before calibration.
What surface finishes work on Pt90Rh10?
No coating needed or possible — clean chemically (hot HCl/dilute nitric plus rinsing) or by flame; polish to mirror finish and avoid contact with graphite, silica-rich supports and reducing furnace atmospheres.
Pt90Rh10 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| RhIEC 60584 / ASTM E1159 Type SP leg | 9.5 – 10.5 | 10 |
| Pdtypical impurity limit, thermocouple grade | ≤ 0 | — |
| Irtypical impurity limit | ≤ 0 | — |
| Fetypical impurity limit | ≤ 0 | — |
| Siembrittling impurity, tightly limited | ≤ 0 | — |
| PtPt + Rh ≥ 99.99 % for thermocouple grade | balance | — |
Pt90Rh10 TC-Class1 — frequently asked
What is Pt90Rh10 TC-Class1 used for?
Pt90Rh10 TC-Class1 is typically used for type S thermocouples, high-temperature furnace sensors and reference thermometry. In short: reference-grade Type S leg; stable to 1450 °C; excellent cold formability (92).
What is the yield strength of Pt90Rh10 TC-Class1?
Pt90Rh10 TC-Class1 has a typical yield strength of 170 MPa (24.7 ksi) and a tensile strength of 320 MPa (46.4 ksi) — weaker than 64% of precious metal grades. Strength varies by condition: see the 6 listed tempers.
Is Pt90Rh10 TC-Class1 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 94% of precious metal grades). Very gummy and expensive — use sharp carbide/diamond tools, light DOC, flood coolant, and capture every chip for refining; wherever possible form from wire/foil instead of cutting.
Can Pt90Rh10 TC-Class1 be welded?
Yes — weldability is rated very good (75/100). Junctions are made by resistance, microplasma, laser or oxy-hydrogen fusion welding without flux; keep the joint free of Si, Fe and Pb contamination to avoid embrittlement and EMF drift.
What surface finishes work on Pt90Rh10 TC-Class1?
No coating needed or possible — clean chemically (hot HCl/dilute nitric plus rinsing) or by flame; polish to mirror finish and avoid contact with graphite, silica-rich supports and reducing furnace atmospheres.
Can Pt90Rh10 TC-Class1 be formed, bent or molded?
Excellent cold formability in the annealed state (drawn below 0.05 mm, rolled to foil); interstage anneal at 900–1100 °C in air, and re-anneal thermocouple wire before calibration.
What is the maximum service temperature of Pt90Rh10 TC-Class1?
Pt90Rh10 TC-Class1 is rated for continuous use to about 1,450°C (2,642 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Pt90Rh10 Annealed and Pt90Rh10 H-Drawn?
Annealed is the default condition — standard stocked condition for S-type thermocouple wire and lab foil: maximum ductility and stable, calibration-conforming EMF. H-Drawn: highest room-temperature strength/stiffness for fine wire handling, springs and electrodes; anneal (or first heat cycle) before use as a calibrated thermocouple. Yield strength is 170 MPa in Annealed versus 620 MPa in H-Drawn.
Sources
- ASTM E1159 — Specification for Thermocouple Materials, Platinum-Rhodium Alloys and Platinum — ASTM (2018)
- ASTM E230/E230M — Standard Specification and Temperature-EMF Tables for Standardized Thermocouples — ASTM (2017)
- IEC 60584-1 Thermocouples — Part 1: EMF specifications and tolerances — IEC (2013)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (precious metals) — ASM International (1990)
- Platinum-rhodium alloy and ZGS PtRh thermophysical data — Johnson Matthey / Heraeus (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.