Standards & Equivalents8–10 min read
ASTM, SAE, EN and UNS Material Numbers Explained
Separate alloy identities, product specifications and test methods before comparing equivalents.
Author: Mat Grades Editorial DeskRead Guide →
EN-GJL-250 Gray Cast Iron
Primary Designation:EN EN-GJL-250
Aliases:
GG-25EN-JL1040Grey Iron 250
Mat Grades internal verification confirms source-backed fidelity and data integrity. It does not constitute external certification or guaranteed lot conformity. Read engineering disclaimer →
Data Completeness:6 composition elements and 9 condition-specific property values cataloged.
Omitted fields represent unverified properties. "Missing is better than invented."
Key Engineering Properties
Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.
Density
7.2 g/cm³TYPICAL · temperature not stated
Thermal Conductivity
46 W/(m·K)TYPICAL · temperature not stated
Specific Heat Capacity
480 J/(kg·K)TYPICAL · temperature not stated
Composition Excerpt
C 3–3.35 wt%Carbon (range)
Standard Elemental Basis: RANGETensile Strength
≥ 250 MPaMINIMUM · As-Cast · temperature not stated
Engineering Summary
EN-GJL-250 (material number EN-JL1040 / former DIN GG-25) is the benchmark European engineering gray cast iron. Engineered with a fully pearlitic matrix structure and controlled Type A graphite distribution, it provides a minimum tensile strength of 250 MPa on 15 mm to 30 mm wall sections, high compressive strength (~800 MPa), exceptional damping capacity, and superior wear resistance. Widely used across European machine tool construction and heavy automotive components.
EN-GJL-250 Gray Cast Iron Documented Applications
- ›Machine tool structural castings (beds, columns, slides, and tables)
- ›High-performance commercial vehicle brake discs and flywheels
- ›Internal combustion engine cylinder blocks, heads, and liners
- ›Industrial pump housings, compressor bodies, and heavy valve bodies
Recognized Aliases
Source-backed commercial trade name and short designations cataloged in canonical data.
GG-25EN-JL1040Grey Iron 250
EN-GJL-250 Gray Cast Iron Specifications & Designations
Standard Designations & Applicable Specifications — Semantically classified designations distinguishing primary standard identifiers, commercial trade names, and applicable specification references.
Direct Standard DesignationsDIRECT DESIGNATION
4 Primary IdentifiersScroll horizontally for full designation data
| System | Identifier | Standard System Name | Classification Notes & Provenance |
|---|---|---|---|
| ENPRIMARY | EN-GJL-250 | European Standard | —Ref: Standard Specifications for Gray and Ductile Cast Iron (ASTM A48/A48M, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, ASM Handbook Vol 1) |
| W-Nr | EN-JL1040 | Werkstoffnummer | —Ref: Standard Specifications for Gray and Ductile Cast Iron (ASTM A48/A48M, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, ASM Handbook Vol 1) |
| DIN | GG-25 | Deutsches Institut für Normung | —Ref: Standard Specifications for Gray and Ductile Cast Iron (ASTM A48/A48M, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, ASM Handbook Vol 1) |
| ISO | 185/JL/250 | International Organization for Standardization | —Ref: Standard Specifications for Gray and Ductile Cast Iron (ASTM A48/A48M, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, ASM Handbook Vol 1) |
Recognized Commercial Aliases & Trade NamesCOMMON ALIAS
3 ListedScroll horizontally for full alias classifications
| Recognized Name / Alias | Classification | Technical Usage & Context |
|---|---|---|
| GG-25 | Historical Alias | Colloquial or commercial industry synonym |
| EN-JL1040 | Commercial Alias | Colloquial or commercial industry synonym |
| Grey Iron 250 | Colloquial Alias | Colloquial or commercial industry synonym |
Applicable Specifications & Product Form ReferencesSPECIFICATION REFERENCE
2 Applicable StandardsScroll horizontally for full standard specifications
| Standards Body | Specification Code | Specification Title / Scope | Relationship Type |
|---|---|---|---|
| CEN | EN 1561 | Founding — Grey cast irons | Specification Reference |
| ISO | ISO 185 | Grey cast irons — Classification | Specification Reference |
Engineering Notice: Applicable specifications establish manufacturing requirements, dimensional tolerances, and test criteria for specific product forms (e.g. bus bar, wire, plate, pipe). They represent applicable technical standards, not alternative or equivalent alloy grades.
EN-GJL-250 Gray Cast Iron Chemical Composition
Chemical Composition (Weight %) — Elemental limits and values from the cited source. Preserves exact semantic limits (minimums, maximums, and ranges).
Scroll horizontally for full elemental limits
| Element | Symbol | Atomic No. | Semantic Basis | Specified Value | Unit | Metallurgical Notes & Qualification | Data Status |
|---|---|---|---|---|---|---|---|
| Carbon | C | 0 | RANGE | 3.00 – 3.35 | wt% | Ref: ASTM International, CEN, ISO & ASM International Standards Technical Committees | VERIFIED |
| Silicon | Si | 0 | RANGE | 1.80 – 2.20 | wt% | Ref: ASTM International, CEN, ISO & ASM International Standards Technical Committees | VERIFIED |
| Manganese | Mn | 0 | RANGE | 0.65 – 0.95 | wt% | Ref: ASTM International, CEN, ISO & ASM International Standards Technical Committees | VERIFIED |
| Phosphorus | P | 0 | MAXIMUM | ≤ 0.12 | wt% | Ref: ASTM International, CEN, ISO & ASM International Standards Technical Committees | VERIFIED |
| Sulfur | S | 0 | MAXIMUM | ≤ 0.12 | wt% | Ref: ASTM International, CEN, ISO & ASM International Standards Technical Committees | VERIFIED |
| Iron | Fe | 0 | REMAINDER | Remainder | wt% | Ref: ASTM International, CEN, ISO & ASM International Standards Technical Committees | VERIFIED |
* Elemental percentages are expressed in weight percent (wt%). Values represent applicable specification limits. Unspecified trace elements are not fabricated or assumed.Preserves exact semantic basis
Property Display UnitsSwitch between Canonical SI and Source / US Customary units:
EN-GJL-250 Gray Cast Iron Physical Properties
Source-specific physical properties. Test temperatures are shown only where reported.
Scroll horizontally for full property parameters
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Density | 7.2 g/cm³ | TYPICAL | 7.2 g/cm³ | ASTM International, CEN & ISO Technical Committees | VERIFIED |
EN-GJL-250 Gray Cast Iron Thermal & Thermodynamic Properties
Phase change temperatures, thermal conductivity, specific heat, mean coefficients of thermal expansion across standardized temperature ranges, and recommended thermal processing windows.
Scroll horizontally for full property parameters
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Thermal Conductivity | 46 W/(m·K) | TYPICAL | 46 W/(m·K) | ASTM International, CEN & ISO Technical Committees | VERIFIED | |
| Specific Heat Capacity | 480 J/(kg·K) | TYPICAL | 480 J/(kg·K) | ASTM International, CEN & ISO Technical Committees | VERIFIED | |
| Coefficient of Thermal Expansion | 11 µm/(m·K) | TYPICAL | 11 µm/(m·K) | ASTM International, CEN & ISO Technical Committees | VERIFIED |
EN-GJL-250 Gray Cast Iron Electrical Properties
Electrical conductivity and resistivity in their reported units and conditions.
Scroll horizontally for full property parameters
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Electrical Resistivity | 660 nΩ·m | TYPICAL | 660 nΩ·m | ASTM International, CEN & ISO Technical Committees | VERIFIED |
EN-GJL-250 Gray Cast Iron Mechanical Properties
Contextual Mechanical Properties & Tempers: Engineering strength, ductility, and hardness values grouped by product form, temper, and section thickness. Mechanical properties are contextual and not isotropic averages.
Elastic & Baseline Mechanical ConstantsSource-specific measurement conditions
Poisson Ratio
0.26 dimensionless
Showing 3 of 3 conditions
Scroll horizontally for all conditions & tempers
| Product Form | Temper / Condition | Section Size | Tensile (UTS) | Yield Strength | Elongation | Shear Strength | Fatigue Strength | Hardness (Scales Preserved) | Status |
|---|---|---|---|---|---|---|---|---|---|
| Standard Product Form | As-CastSource values and qualifiersUltimate Tensile Strength: ≥ 250 MPa (MINIMUM)Governing minimum tensile strength per EN 1561 for 15–30 mm wall thickness. No yield point.ASTM International, CEN, ISO & ASM International Standards Technical Committees — ASTM A48, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, ASM Handbook Vol 1 | — · 15 mm to 30 mm wall thickness | ≥ 250 MPa | — | — | — | — | — | VERIFIED |
| Standard Product Form | As-CastSource values and qualifiers | — | — | — | — | — | — | — | VERIFIED |
| Standard Product Form | As-CastSource values and qualifiers | — | — | — | — | — | — | 180–230 HBW | VERIFIED |
Hardness Integrity Notice: Rockwell B (HRB), Rockwell F (HRF), and Superficial 30T (HR30T) scales are reported on their measured scales without cross-scale mathematical conversion.
Source: See fact-level citations
EN-GJL-250 Gray Cast Iron Processing & Fabrication
Machining, joining, forming, and thermal processing ratings cataloged from the cited authoritative technical reference.
Machinability
Good machinability (~85% of C36000 baseline). Fully pearlitic matrix provides clean, burr-free surfaces on machined slideways.
Weldability & Joining
Poor weldability. Requires preheating (300°C) and qualified repair procedures to avoid brittle white iron at the fusion line.
Heat Treatment & Working Ranges
Stress relief at 550°C–600°C for 2 hours to ensure dimensional stability. Slideways can be induction surface hardened to 50–55 HRC.
Forming & Cold Working
Non-deformable.
Practical Engineering & Fabrication Notes
By Mat Grades Editorial Desk · Updated 2026-11-14. Use alongside the specified product standard and supplier certificate.
Machining & shop-floor behavior
The cataloged machining note for EN-GJL-250 Gray Cast Iron states: Good machinability (~85% of C36000 baseline). Fully pearlitic matrix provides clean, burr-free surfaces on machined slideways. A relevant hardness example is HBW Hardness: 180–230 HBW (range; As-Cast). Use that supplied condition for a trial of the difficult feature. Record tool changes, burr removal, unclamped dimensions and accepted parts per hour. Relative machinability ratings from different reference scales should not be compared as if they were one common test.
Weldability, brazing & joining
The available joining assessment states: Poor weldability. Requires preheating (300°C) and qualified repair procedures to avoid brittle white iron at the fusion line. The first cataloged strength example is Ultimate Tensile Strength: minimum 250 MPa (minimum; As-Cast). Assess the final part after joining or thermal processing. Include distortion, cleanup and inspection in the quotation. A material designation or favorable process rating is a starting point for qualification, not evidence that an untested joint meets the drawing.
Corrosion & service environment
Consider moisture, coating, local tensile stress and impact as well as the cast-iron family. Surface protection does not repair porosity or a highly stressed transition. Casting section and sampling arrangement affect how coupon evidence relates to the finished component; keep those limits visible in the approval. The recorded thermal example is Thermal Conductivity: 46 W/(m·K) (typical; additional condition not stated). State the exposure and inspection access in the design record so that a change of installation or cleaning method triggers a review. The selected composition entries are C 3–3.35 wt%, Si 1.8–2.2 wt%, Mn 0.65–0.95 wt%. Chemistry documents identity; it does not establish fluid compatibility.
Selection trade-offs & applications
Use EN EN-GJL-250, W-Nr EN-JL1040, DIN GG-25 to identify the candidate, then specify the product form and delivered condition separately. The catalog lists Machine tool structural castings (beds, columns, slides, and tables) as an application example. The related candidate ASTM A48 Class 35 Gray Cast Iron is linked for comparison; its approximate equivalent relationship must be checked before substitution. Compare the complete route through machining, joining, finish and inspection. Keep the certificate, required test location and acceptance criteria with the first-article record. A later change of grade, condition or source should be assessed against that same requirement.
Technical references: ASTM International, CEN, ISO & ASM International Standards Technical Committees
EN-GJL-250 Gray Cast Iron Equivalent & Comparable Grades
Comparable Grades & Cross-References: Carefully classified cross-reference relationships for EN-GJL-250 Gray Cast Iron. Comparable does not mean equivalent.
Scroll horizontally for relationship classifications & comparisons
| Related Material | Family | Relationship Classification | Metallurgical Notes & Differences | Status | Action |
|---|---|---|---|---|---|
| ASTM A48 Class 35 Gray Cast Iron | Cast Iron | Approximate Equivalent | EN-GJL-250 (min 250 MPa tensile on 15–30 mm wall) closely mirrors ASTM A48 Class 35 (min 241 MPa on 30.5 mm Test Bar B) in microstructure, hardness, and machine tool engineering service.Engineering substitution review required. Design calculations must verify temper, formability, and corrosion limits before specifying as a direct replacement. | VERIFIED | |
| EN-GJS-500-7 Ductile Cast Iron | Cast Iron | Commonly Compared | Comparison of flake vs spheroidal graphite: EN-GJL-250 provides higher vibration damping, thermal conductivity, and machinability, while EN-GJS-500-7 offers double the tensile strength (500 vs 250 MPa) and true elongation (7%).Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost). | VERIFIED |
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Sources
Sources & Provenance Trail: Authoritative reference publications, standards specifications, and data registers cited across this material record.
ASTM International, CEN & ISO Technical CommitteesStandard Specifications for Gray and Ductile Cast Iron (ASTM A48/A48M, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, ASM Handbook Vol 1)
STANDARDS ORG
Authoritative foundry data harmonized across ASTM A48, ASTM A536, EN 1561, EN 1563, ISO 185, ISO 1083, SAE J431, SAE J434, and ASM International Handbook Volume 1 (Properties and Selection: Irons, Steels, and High-Performance Alloys).
Issuing Body: ASTM International, CEN, ISO & ASM International Standards Technical CommitteesRevision: ASTM A48/A48M-22 / ASTM A536-84(2024) / EN 1561:2020 / EN 1563:2018 / ISO 185:2020 / ISO 1083:2018View Source Record ↗
Intellectual Property & Provenance Notice: Mat Grades cites technical literature from recognized industry associations and standards organizations. Underlying technical standards and publication data remain the intellectual property of their respective issuing organizations.