Steel 4J36 HotRolled
Finish state
GB 4J36 · UNS K93600
Rough stock for thick plate, blocks and mould bases that will be machined and then stabilized.
Values for the HotRolled condition
Other 4J36 tempers and conditions
4J36 is listed in 5 conditions; see the grade overview at 4J36.
- Annealed
- HotRolled
- Stabilized
- 1/2H
- ColdDrawn
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 | — |
HotRolledThis page 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 |
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 HotRolled?
4J36 HotRolled is 4J36 supplied in the HotRolled condition — rough stock for thick plate, blocks and mould bases that will be machined and then stabilized. 4J36 HotRolled 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 141 GPa (20.5 Msi). 4J36 HotRolled 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; HotRolled 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
- Readily welded — 75/100, better than 76% 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 — 141 GPa (20.5 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 HotRolled properties
Typical room-temperature values for 4J36 HotRolled; 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 HotRolled 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 HotRolled 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 141 GPa (20.5 Msi).
Thermal6
4J36 HotRolled 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 1.7 µm/m·K (0.944 µin/in·°F).
Electrical3
4J36 HotRolled 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 HotRolled 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 HotRolled's machinability is poor (30/100, worse than 89% of steel grades); weldability very good (75/100); 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 HotRolled
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 HotRolled — frequently asked
What is 4J36 HotRolled used for?
4J36 HotRolled 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 HotRolled?
4J36 HotRolled 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 HotRolled 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 HotRolled be welded?
Yes — weldability is rated very good (75/100). 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 HotRolled?
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 HotRolled 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 HotRolled?
4J36 HotRolled 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.