Steel 4J36 Stabilized
Heat-treated state
GB 4J36 · UNS K93600
Specify for gauge blocks, laser benches and metrology parts needing the lowest CTE and long-term dimensional stability (minimal creep/growth).
Values for the Stabilized condition
Other 4J36 tempers and conditions
4J36 is listed in 5 conditions; see the grade overview at 4J36.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault solution/soft annealed, 830 °C water or air cooled | Standard stock condition for plate, sheet, bar and forgings; best ductility and lowest, most reproducible expansion after subsequent stabilizing. | 280 | 490 | 40 | 135 HB | — |
Hot rolled / hot forged, as-worked | Rough stock for thick plate, blocks and mould bases that will be machined and then stabilized. | 300 | 500 | 35 | 150 HB | 2.2 % IACS |
StabilizedThis page 830 °C anneal + 315 °C stress relief + 95 °C ageing | Specify for gauge blocks, laser benches and metrology parts needing the lowest CTE and long-term dimensional stability (minimal creep/growth). | 300 | 500 | 35 | 140 HB | 2.2 % IACS |
Half hard | Intermediate strength strip, bar and tube where some springback and stiffness are wanted with usable ductility. | 450 | 620 | 20 | 12 HRC | 2.1 % IACS |
heavily cold worked bar, wire, strip, tube | Choose for maximum strength and straightness in wire, small bar and thin-wall tube; expansion is slightly reduced but internal stress must be relieved for precision parts. | 650 | 800 | 8 | 24 HRC | — |
What is 4J36 Stabilized?
4J36 Stabilized is 4J36 heat treated to Stabilized — specify for gauge blocks, laser benches and metrology parts needing the lowest CTE and long-term dimensional stability (minimal creep/growth). 4J36 Stabilized has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 86% of steel grades. Elongation at break is 35% and the elastic modulus is 145 GPa (21 Msi). 4J36 Stabilized has a density of 8.1 g/cm³ (0.293 lb/in³), heavier than 97% of steel grades. It melts at 1,427°C (2,601 °F). Annealed is the default condition FabDigit quotes; Stabilized is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 35%, better than 97% of steel grades
- Good corrosion resistance — 25/100, better than 92% of steel grades
- Forms and bends easily — 70/100, better than 86% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Poor heat conductor — 10.5 W/m·K (6.07 BTU/hr·ft·°F), worse than 100% of steel grades
- Low stiffness — 145 GPa (21 Msi), worse than 98% of steel grades
- Low electrical conductivity — 2.2 % IACS, worse than 98% of steel grades
- High embodied carbon — 5.5 kg CO₂/kg, worse than 97% of steel grades
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
4J36 Stabilized properties
Typical room-temperature values for 4J36 Stabilized; 21 are specific to this condition. Other listed values are 4J36 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
4J36 Stabilized has a density of 8.1 g/cm³ (0.293 lb/in³), heavier than 97% of steel grades. It melts at 1,427°C (2,601 °F).
Mechanical14
4J36 Stabilized has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 86% of steel grades. Elongation at break is 35% and the elastic modulus is 145 GPa (21 Msi).
Thermal6
4J36 Stabilized is rated for continuous service to 200°C (392 °F). It conducts heat at 10.5 W/m·K (6.07 BTU/hr·ft·°F), worse than 100% of steel grades. Thermal expansion is 1.1 µm/m·K (0.611 µin/in·°F).
Electrical3
4J36 Stabilized conducts electricity at 2.2 % IACS, worse than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (25/100), better than 92% of steel grades.
Sustainability4
Producing a kilogram of 4J36 Stabilized takes about 75 MJ of energy and emits 5.5 kg of CO₂ — more than 97% of steel grades. Typical recycled content is 30%.
Manufacturability8
4J36 Stabilized's machinability is poor (30/100, worse than 89% of steel grades); weldability good (60/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 4J36 Stabilized
Is 4J36 easy to machine?
Gummy and work-hardening: use sharp positive-rake carbide, rigid setup, low speed (20–35 m/min) with heavy constant feed and flood coolant; avoid dwelling to prevent glazing.
Can 4J36 be welded?
GTAW/EBW/laser with matching 36Ni filler and low heat input; keep interpass low and joints clean — sulfur, carbon or oil pickup causes hot cracking.
Can 4J36 be formed, bent or molded?
Excellent cold formability — deep drawing, bending and spinning are routine; anneal at 830 °C between heavy reductions.
What surface finishes work on 4J36?
Not corrosion resistant — protect with electroless nickel, chrome plating, passivation or paint; polishes reasonably well but must be stabilized after machining to hold dimensions.
4J36 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 |
|---|---|---|
| NiInvar composition window; some standards allow 35.0–37.0 | 35 – 36.5 | 36 |
| C | ≤ 0.05 | 0.03 |
| Si | ≤ 0.3 | 0.15 |
| Mn | 0.2 – 0.6 | 0.4 |
| P | ≤ 0.02 | — |
| S | ≤ 0.02 | — |
| Crresidual | ≤ 0.15 | — |
| Curesidual | ≤ 0.2 | — |
| Coresidual; Co is deliberately added only in 4J32 Super-Invar | ≤ 0.5 | — |
| Fe | balance | — |
4J36 Stabilized — frequently asked
What is 4J36 Stabilized used for?
4J36 Stabilized is typically used for precision molds/tooling, measuring tapes and gauges, bimetal strips and cryogenic vessels. In short: classic Invar 36 grade; most widely stocked low-expansion alloy; cryogenic-capable.
What is the yield strength of 4J36 Stabilized?
4J36 Stabilized has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 86% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 4J36 Stabilized easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% of steel grades). Gummy and work-hardening: use sharp positive-rake carbide, rigid setup, low speed (20–35 m/min) with heavy constant feed and flood coolant; avoid dwelling to prevent glazing.
Can 4J36 Stabilized be welded?
Yes — weldability is rated good (60/100). GTAW/EBW/laser with matching 36Ni filler and low heat input; keep interpass low and joints clean — sulfur, carbon or oil pickup causes hot cracking.
What surface finishes work on 4J36 Stabilized?
Not corrosion resistant — protect with electroless nickel, chrome plating, passivation or paint; polishes reasonably well but must be stabilized after machining to hold dimensions.
Can 4J36 Stabilized be formed, bent or molded?
Excellent cold formability — deep drawing, bending and spinning are routine; anneal at 830 °C between heavy reductions.
What is the maximum service temperature of 4J36 Stabilized?
4J36 Stabilized is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM F1684 Standard Specification for Iron-Nickel and Iron-Nickel-Cobalt Alloys for Low Thermal Expansion Applications — ASTM (2020)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Low-Expansion Alloys) — ASM International (1990)
- Invar 36 / Pernifer 36 alloy datasheet — specialty alloy producers (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.