Steel 30KhGSL-SR (Stress relieved)
Heat-treated state
GOST 30KhGSL
Used after weld repair or rough machining of large castings to remove residual stress without changing strength much.
Values for the SR condition
Other 30KhGSL tempers and conditions
30KhGSL is listed in 7 conditions; see the grade overview at 30KhGSL.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Chosen for maximum machinability and stress relief before final quench-and-temper. | 320 | 560 | 18 | 11 HRC | 8 % IACS |
SRThis page Stress relieved | Used after weld repair or rough machining of large castings to remove residual stress without changing strength much. | 370 | 610 | 12 | 15 HRC | 7.8 % IACS |
Spheroidize annealed | Rough/unstressed castings only; coarse dendritic structure with residual casting stresses and low toughness. | 380 | 620 | 8 | 19 HRC | 7.8 % IACS |
N+TDefault Normalized and tempered | Standard supply condition for GOST 977 structural castings — balanced strength, ductility and impact toughness. | 430 | 650 | 15 | 207 HB | — |
Normalized | Grain refinement of the as-cast structure; intermediate step or economical condition for lightly loaded castings. | 450 | 700 | 12 | 20 HRC | 7.7 % IACS |
Q&T | Main high-duty condition: sorbitic structure giving ~800 MPa UTS with retained toughness for shafts, levers and mining parts. | 640 | 820 | 12 | 25 HRC | — |
Q&T | Selected when maximum strength/wear resistance is needed and section sizes are moderate; toughness drops noticeably. | 830 | 1,000 | 9 | 33 HRC | — |
What is 30KhGSL-SR?
30KhGSL-SR is 30KhGSL heat treated to SR — used after weld repair or rough machining of large castings to remove residual stress without changing strength much. 30KhGSL-SR has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 610 MPa (88.5 ksi) — weaker than 70% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi). 30KhGSL-SR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). N+T is the default condition FabDigit quotes; SR is available on request or by drawing note.
Limitations
- Limited formability — 14/100, worse than 90% of steel grades
- Limited ductility — 12%, worse than 84% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
- Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 82% of steel grades
30KhGSL-SR properties
Typical room-temperature values for 30KhGSL-SR; 23 are specific to this condition. Other listed values are 30KhGSL reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
30KhGSL-SR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
30KhGSL-SR has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 610 MPa (88.5 ksi) — weaker than 70% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
30KhGSL-SR is rated for continuous service to 400°C (752 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
30KhGSL-SR conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 30KhGSL-SR takes about 27 MJ of energy and emits 2.1 kg of CO₂ — less than 59% of steel grades. Typical recycled content is 70%.
Manufacturability8
30KhGSL-SR's machinability is fair (50/100, worse than 53% of steel grades); weldability fair (42/100); formability not recommended (14/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 30KhGSL-SR
Is 30KhGSL easy to machine?
Machine in the annealed or N+T condition with carbide tooling at moderate speeds; hard skin and sand inclusions on the as-cast surface dull tools quickly, so take a heavy first cut.
Can 30KhGSL be welded?
Limited weldability (CE ≈ 0.7–0.8): use low-hydrogen consumables, 250–350 °C preheat, controlled interpass and a 600–650 °C post-weld temper to avoid HAZ cracking.
Can 30KhGSL be formed, bent or molded?
Sand or shell casting with generous risering and chills; the Cr-Mn-Si chemistry is hot-tear and shrinkage sensitive, so keep uniform sections and avoid abrupt junctions.
What surface finishes work on 30KhGSL?
Not anodizable — protect by shot blasting followed by phosphating, zinc-rich primer/paint or hard chrome/nitriding on wear surfaces.
30KhGSL 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 |
|---|---|---|
| C | 0.25 – 0.35 | 0.3 |
| Si | 0.6 – 0.8 | 0.7 |
| Mn | 0.9 – 1.2 | 1.05 |
| Cr | 0.6 – 0.9 | 0.75 |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.3 | — |
| S | ≤ 0.04 | — |
| P | ≤ 0.04 | — |
| Fe | balance | — |
30KhGSL-SR — frequently asked
What is 30KhGSL-SR used for?
30KhGSL-SR is typically used for heavy machinery structural castings, tank/vehicle components and gear blanks. In short: GOST high-strength cast steel; limited weldability, high CE; best machinability in family.
What is the yield strength of 30KhGSL-SR?
30KhGSL-SR has a typical yield strength of 370 MPa (53.7 ksi) and a tensile strength of 610 MPa (88.5 ksi) — weaker than 70% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 30KhGSL-SR easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine in the annealed or N+T condition with carbide tooling at moderate speeds; hard skin and sand inclusions on the as-cast surface dull tools quickly, so take a heavy first cut.
Can 30KhGSL-SR be welded?
With care — weldability is rated fair (42/100). Limited weldability (CE ≈ 0.7–0.8): use low-hydrogen consumables, 250–350 °C preheat, controlled interpass and a 600–650 °C post-weld temper to avoid HAZ cracking.
What surface finishes work on 30KhGSL-SR?
Not anodizable — protect by shot blasting followed by phosphating, zinc-rich primer/paint or hard chrome/nitriding on wear surfaces.
Can 30KhGSL-SR be formed, bent or molded?
Sand or shell casting with generous risering and chills; the Cr-Mn-Si chemistry is hot-tear and shrinkage sensitive, so keep uniform sections and avoid abrupt junctions.
What is the maximum service temperature of 30KhGSL-SR?
30KhGSL-SR is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 30KhGSL N+T and 30KhGSL-QT500?
N+T is the default condition — standard supply condition for GOST 977 structural castings — balanced strength, ductility and impact toughness. QT500: selected when maximum strength/wear resistance is needed and section sizes are moderate; toughness drops noticeably. Yield strength is 430 MPa in N+T versus 830 MPa in QT500.
Sources
- GOST 977-88 — Steel castings. General specifications — Gosstandart (1988)
- Marochnik stalej i splavov — 30ХГСЛ cast steel data sheet — Marochnik (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys (cast low-alloy steels) — ASM International (1990)
- GB/T 14408 / GB/T 5680 low-alloy steel castings (comparison grade ZG30CrMnSi) — SAC (2014)
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.