Steel GX5NiS36 STAB
Heat-treated state
EN 1.3963
STAB = dimensionally stabilized
Three-step Invar stabilizing cycle for metrology frames, gauges and optical benches where microstrain drift over years must be minimised.
Values for the STAB condition
Other GX5NiS36 tempers and conditions
GX5NiS36 is listed in 5 conditions; see the grade overview at GX5NiS36.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest and most ductile state; used when maximum machining ease and a homogeneous, low-scatter expansion coefficient are wanted before final stabilizing. | 180 | 400 | 15 | 125 HB | 2.2 % IACS |
SRDefault Stress relieved | Standard delivery condition: removes casting residual stress so parts hold shape through rough and finish machining. | 200 | 420 | 12 | 135 HB | 2.1 % IACS |
Hot isostatic pressed | Optional densification for pressure-tight or fatigue-loaded castings; closes microporosity and raises ductility, at extra cost. | 210 | 450 | 18 | 140 HB | 2.2 % IACS |
As fabricated | Cheapest condition for rough or non-critical low-expansion castings that will be stress-relieved after machining anyway. | 215 | 430 | 10 | 145 HB | 2.1 % IACS |
STABThis page Dimensionally stabilized | Three-step Invar stabilizing cycle for metrology frames, gauges and optical benches where microstrain drift over years must be minimised. | 220 | 430 | 13 | 140 HB | 2.1 % IACS |
What is GX5NiS36 STAB?
GX5NiS36 STAB is GX5NiS36 heat treated to STAB — three-step Invar stabilizing cycle for metrology frames, gauges and optical benches where microstrain drift over years must be minimised. GX5NiS36 STAB has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 430 MPa (62.4 ksi) — weaker than 98% of steel grades. Elongation at break is 13% and the elastic modulus is 142 GPa (20.6 Msi). GX5NiS36 STAB has a density of 8.1 g/cm³ (0.293 lb/in³), heavier than 97% of steel grades. It melts at 1,425°C (2,597 °F). SR is the default condition FabDigit quotes; STAB is available on request or by drawing note.
Advantages
- Good corrosion resistance — 30/100, better than 95% of steel grades
Limitations
- Poor heat conductor — 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 99% of steel grades
- Low electrical conductivity — 2.1 % IACS, worse than 99% of steel grades
- High embodied carbon — 8.5 kg CO₂/kg, worse than 99% of steel grades
- Low strength — 220 MPa (31.9 ksi), worse than 98% of steel grades
- Low stiffness — 142 GPa (20.6 Msi), worse than 98% of steel grades
GX5NiS36 STAB properties
Typical room-temperature values for GX5NiS36 STAB; 21 are specific to this condition. Other listed values are GX5NiS36 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
GX5NiS36 STAB has a density of 8.1 g/cm³ (0.293 lb/in³), heavier than 97% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
GX5NiS36 STAB has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 430 MPa (62.4 ksi) — weaker than 98% of steel grades. Elongation at break is 13% and the elastic modulus is 142 GPa (20.6 Msi).
Thermal6
GX5NiS36 STAB is rated for continuous service to 200°C (392 °F). It conducts heat at 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 99% of steel grades. Thermal expansion is 2.5 µm/m·K (1.39 µin/in·°F).
Electrical3
GX5NiS36 STAB conducts electricity at 2.1 % IACS, worse than 99% of steel grades.
Chemical & Environmental2
Corrosion resistance is poor (30/100), better than 95% of steel grades.
Sustainability4
Producing a kilogram of GX5NiS36 STAB takes about 110 MJ of energy and emits 8.5 kg of CO₂ — more than 99% of steel grades. Typical recycled content is 35%.
Manufacturability7
GX5NiS36 STAB's machinability is fair (38/100, worse than 80% of steel grades); weldability poor (25/100); formability not recommended (10/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with GX5NiS36 STAB
Is GX5NiS36 easy to machine?
Best of the Invar family: run sharp positive-rake carbide at low speed (roughly 25–50 m/min) with heavy flood coolant; the MnS inclusions break chips and reduce the gummy built-up edge typical of Invar 36.
Can GX5NiS36 be welded?
Poor — sulfur strongly promotes solidification cracking; if unavoidable use matched low-S Invar filler, low heat input, preheat-free, and expect a HAZ with degraded expansion behaviour.
Can GX5NiS36 be formed, bent or molded?
A casting alloy only: sand or investment cast with generous risers because of the long freezing range; no meaningful cold formability.
What surface finishes work on GX5NiS36?
Not corrosion resistant — protect with oil, paint, electroless Ni or chrome plate; polished surfaces show sulfide pull-out, so lapping needs fine grit and patience.
GX5NiS36 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 |
|---|---|---|
| CGX5 designation ≈ 0.05 % C | ≤ 0.07 | 0.05 |
| Si | ≤ 0.6 | 0.3 |
| Mnmust be sufficient to tie up S as MnS | 0.2 – 0.8 | 0.5 |
| P | ≤ 0.03 | 0.02 |
| Sdeliberate free-machining addition | 0.15 – 0.35 | 0.25 |
| Nicontrols the Invar minimum in CTE | 35 – 37 | 36 |
| Coresidual | ≤ 0.5 | — |
| Crresidual; raises CTE | ≤ 0.3 | — |
| Fe | balance | — |
GX5NiS36 STAB — frequently asked
What is GX5NiS36 STAB used for?
GX5NiS36 STAB is typically used for machined low-expansion tooling castings, precision jigs and fixtures and measurement standard castings. In short: best-machining cast Invar; free-machining Fe-36Ni casting; poor weldability.
What is the yield strength of GX5NiS36 STAB?
GX5NiS36 STAB has a typical yield strength of 220 MPa (31.9 ksi) and a tensile strength of 430 MPa (62.4 ksi) — weaker than 98% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is GX5NiS36 STAB easy to machine?
Not especially — machinability is rated fair (38/100, worse than 80% of steel grades). Best of the Invar family: run sharp positive-rake carbide at low speed (roughly 25–50 m/min) with heavy flood coolant; the MnS inclusions break chips and reduce the gummy built-up edge typical of Invar 36.
Can GX5NiS36 STAB be welded?
Not readily — weldability is rated poor (25/100). Poor — sulfur strongly promotes solidification cracking; if unavoidable use matched low-S Invar filler, low heat input, preheat-free, and expect a HAZ with degraded expansion behaviour.
What surface finishes work on GX5NiS36 STAB?
Not corrosion resistant — protect with oil, paint, electroless Ni or chrome plate; polished surfaces show sulfide pull-out, so lapping needs fine grit and patience.
Can GX5NiS36 STAB be formed, bent or molded?
A casting alloy only: sand or investment cast with generous risers because of the long freezing range; no meaningful cold formability.
What is the maximum service temperature of GX5NiS36 STAB?
GX5NiS36 STAB 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.
What is the difference between GX5NiS36-SR and GX5NiS36-A?
SR is the default condition — standard delivery condition: removes casting residual stress so parts hold shape through rough and finish machining. A: softest and most ductile state; used when maximum machining ease and a homogeneous, low-scatter expansion coefficient are wanted before final stabilizing. Yield strength is 200 MPa in SR versus 180 MPa in A.
Sources
- SEW 385 — Physikalisch bestimmte Eisenlegierungen (Fe-Ni low-expansion cast and wrought alloys) — Verein Deutscher Eisenhüttenleute (VDEh) (1993)
- DIN 17745 — Nickel-Eisen-Knetlegierungen mit vorgeschriebener Wärmeausdehnung — DIN (2002)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Low-Expansion Alloys) — ASM International (1990)
- Cast Invar / free-machining Fe-36Ni foundry alloy data — European low-expansion alloy foundries (2020)
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.