Nickel Alloy Chromel
Chromel is the Ni-10Cr positive leg of Type K thermocouples, supplied as E230 Type K (+) / Type KP wire and paired with Alumel.
Reference datasheet — Chromel is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the Annealed condition
Chromel tempers and conditions
Chromel is supplied in 6 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault soft, fully recrystallized thermocouple wire | Standard stocked condition for thermocouple wire, extension/compensating cable conductor and MI-cable cores; best emf stability and bendability. | 275 | 655 | 35 | 80 HRB | — |
Standard limits of error | Ordinary calibration grade for general industrial K-type thermocouples and extension wire. | 275 | 655 | 35 | 150 HB | 2.4 % IACS |
Stress relieved | Low-temperature stabilizing treatment after coiling or forming to remove cold-work drift and restore calibrated thermoelectric output. | 330 | 700 | 30 | 160 HB | 2.4 % IACS |
Quarter hard | Choose when slightly stiffer wire is needed for automatic winding or probe assembly while retaining good ductility. | 480 | 760 | 20 | 190 HB | 2.4 % IACS |
Half hard | Stiffer wire and strip for self-supporting sensor elements and formed contacts; anneal after forming to restore emf stability. | 690 | 900 | 10 | 21 HRC | 2.3 % IACS |
Hard Drawn | Maximum strength and springiness for resistance/heating windings and fine wire handling; emf output shifts slightly until stress-relieved. | 900 | 1,100 | 3 | 28 HRC | 2.4 % IACS |
Supply forms, finishes and certifications
Ways Chromel is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
SLE | Special limits of error | Certification |
What is Chromel?
Chromel is the Ni-10Cr positive leg of Type K thermocouples, supplied as E230 Type K (+) / Type KP wire and paired with Alumel. Engineers specify it for its stable Seebeck coefficient over a wide temperature range and its very good drawability, with wire available annealed, 1/4H, 1/2H, hard-drawn and stress-relieved in standard (STD) or special limits of error (SLE) tolerance classes. Service is limited to 1100 °C and to clean oxidising or inert atmospheres; sulphur contamination and residual cold work shift emf, and the alloy is not used as a structural material. Chromel has a density of 8.73 g/cm³ (0.315 lb/in³), heavier than 77% of nickel alloy grades. It melts at 1,400°C (2,552 °F). Chromel has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 83% of nickel alloy grades. Elongation at break is 35% and the elastic modulus is 186 GPa (27 Msi).
What is Chromel used for?
- Type K thermocouples
- Temperature sensor wire
- Mineral-insulated thermocouple cable conductors
- Furnace and kiln thermocouple probes
- Type K extension and compensating cable
- Surface and immersion sensor assemblies
Advantages
- Forms and bends easily — 90/100, better than 98% of nickel alloy grades
- High service temperature — 1,100°C (2,012 °F), better than 88% of nickel alloy grades
- Conducts heat well — 19.2 W/m·K (11.1 BTU/hr·ft·°F), better than 86% of nickel alloy grades
- High electrical conductivity — 2.4 % IACS, better than 84% of nickel alloy grades
Limitations
- Low strength — 275 MPa (39.9 ksi), worse than 83% of nickel alloy grades
- Needs corrosion protection — 68/100, worse than 82% of nickel alloy grades
Chromel properties
Typical room-temperature values for Chromel-Annealed; bars are the position among nickel alloy grades.
Physical3
Chromel has a density of 8.73 g/cm³ (0.315 lb/in³), heavier than 77% of nickel alloy grades. It melts at 1,400°C (2,552 °F).
Mechanical13
Chromel has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 83% of nickel alloy grades. Elongation at break is 35% and the elastic modulus is 186 GPa (27 Msi).
Thermal6
Chromel is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 19.2 W/m·K (11.1 BTU/hr·ft·°F), better than 86% of nickel alloy grades. Thermal expansion is 13.1 µm/m·K (7.28 µin/in·°F).
Electrical3
Chromel conducts electricity at 2.4 % IACS, better than 84% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), worse than 82% of nickel alloy grades.
Sustainability4
Producing a kilogram of Chromel takes about 175 MJ of energy and emits 12.5 kg of CO₂ — more than 65% of nickel alloy grades. Typical recycled content is 25%.
Manufacturability8
Chromel's machinability is poor (28/100, better than 82% of nickel alloy grades); weldability very good (75/100); formability excellent (90/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the nickel alloy family
Yield strength against density for every nickel alloy grade FabDigit runs. Chromel is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Chromel
Is Chromel easy to machine?
Gummy austenitic Ni-Cr solid solution — use sharp positive-rake carbide, rigid setups, low speed with heavy positive feed and flood coolant to avoid work hardening; rarely machined since the alloy is sold as wire.
Can Chromel be welded?
Readily joined by capacitor-discharge, resistance or TIG welding of the thermocouple junction; keep the hot junction free of dissimilar filler and avoid sulphur-bearing fluxes.
Can Chromel be formed, bent or molded?
Excellent cold drawability and bendability in the annealed temper (down to fine gauges); interanneal cold-worked wire and stress-relieve after coiling to recover emf accuracy.
Chromel 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 |
|---|---|---|
| Crgives the positive Seebeck slope and oxidation resistance | 9 – 10.5 | 10 |
| Fe | ≤ 0.5 | 0.2 |
| Sideoxidizer, small emf effect | ≤ 0.4 | 0.2 |
| Mn | ≤ 0.5 | 0.2 |
| C | ≤ 0.15 | 0.05 |
| Skept low to avoid sulphur embrittlement | ≤ 0.02 | |
| Nibalance, nominally ~90 % | balance |
What surface finishes work on Chromel?
Not anodizable; pre-oxidation in clean air forms a protective Cr₂O₃ film, and wire can be electroplated or glass/ceramic-fibre or MgO-insulated for service.
Surface treatments FabDigit runs on nickel alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Nickel Alloy Chromel in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- Chromel / KP
How much does Chromel cost?
Chromel is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Chromel — frequently asked
What is Chromel used for?
Chromel is typically used for type K thermocouples, temperature sensor wire, mineral-insulated thermocouple cable conductors, furnace and kiln thermocouple probes, type K extension and compensating cable and surface and immersion sensor assemblies. In short: type K positive leg; stable emf to 1100 °C; excellent fine-wire drawability.
What is the yield strength of Chromel?
Chromel has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 83% of nickel alloy grades. Strength varies by condition: see the 6 listed tempers.
Is Chromel easy to machine?
Not especially — machinability is rated poor (28/100, better than 82% of nickel alloy grades). Gummy austenitic Ni-Cr solid solution — use sharp positive-rake carbide, rigid setups, low speed with heavy positive feed and flood coolant to avoid work hardening; rarely machined since the alloy is sold as wire.
Can Chromel be welded?
Yes — weldability is rated very good (75/100). Readily joined by capacitor-discharge, resistance or TIG welding of the thermocouple junction; keep the hot junction free of dissimilar filler and avoid sulphur-bearing fluxes.
What surface finishes work on Chromel?
Not anodizable; pre-oxidation in clean air forms a protective Cr₂O₃ film, and wire can be electroplated or glass/ceramic-fibre or MgO-insulated for service.
Can Chromel be formed, bent or molded?
Excellent cold drawability and bendability in the annealed temper (down to fine gauges); interanneal cold-worked wire and stress-relieve after coiling to recover emf accuracy.
What is the maximum service temperature of Chromel?
Chromel is rated for continuous use to about 1,100°C (2,012 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Chromel Annealed and Chromel-HD?
Annealed is the default condition — standard stocked condition for thermocouple wire, extension/compensating cable conductor and MI-cable cores; best emf stability and bendability. HD: maximum strength and springiness for resistance/heating windings and fine wire handling; emf output shifts slightly until stress-relieved. Yield strength is 275 MPa in Annealed versus 900 MPa in HD.
How much does Chromel cost?
Chromel is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM E230/E230M — Standard Specification and Temperature-EMF Tables for Standardized Thermocouples — ASTM International (2023)
- IEC 60584-1 Thermocouples — EMF specifications and tolerances — IEC (2013)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- Thermocouple alloy physical property tables (Chromel/Alumel type K legs) — Hoskins / Omega Engineering (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.