When sourcing engineering materials globally, the same alloy often appears under different national codes — SAE 4140 (US), DIN 42CrMo4 (Germany), BS EN 19 (UK), JIS SCM440 (Japan), and AS 1444 4140 (Australia) all describe the same low-alloy chromium-molybdenum steel. The ISO VDI 3323 system groups materials by metallurgical behaviour (groups 1 through 41+) and is the international spine for cutting tool selection, speeds and feeds, and procurement cross-reference.
This reference covers the major engineering material groups with cross-walks to SAE/AISI (US), DIN (Germany), BS EN (UK), AFNOR (France), JIS (Japan), and the Australian Standard equivalents — the AS/NZS layer many international cross-reference charts omit but which matters for AU procurement.
ISO VDI 3323 Material Groups — Master Cross-Reference Table
The headline reference. Each row maps one ISO VDI 3323 material group to its national-standard equivalents. Cross-references are nearest-equivalent matches; chemistry typically aligns within standard tolerance, but mechanical properties may differ slightly between national standards — verify against the specific standard for procurement-critical decisions.
| ISO VDI 3323 Group | Material Description | Typical Application | SAE / AISI / UNS (US) | DIN (Germany) | BS EN (UK) | AFNOR (France) | JIS (Japan) | AS/NZS (Australia) | Condition Note |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Low-carbon steel, non-alloy (~0.15% C) | Mild steel, general fabrication, weldable structural | SAE 1015 / 1018 / 1020 | DIN C15 (1.0401), Ck15 (1.1141) | BS EN 080 M 15, EN 32C | AFNOR XC12 / CC12 | JIS S15C / S20C | AS 1442 K1015 / K1018 / K1020 | Annealed or as-rolled |
| 2-3 | Medium-carbon steel, non-alloy (~0.45% C) | Shafts, axles, gears, heat-treatable | SAE 1045 / 1050 | DIN C45 (1.0503), Ck45 (1.1191) | BS EN 080 M 46, EN 8 | AFNOR XC42 / CC45 | JIS S45C / S48C | AS 1442 K1045 | Annealed or quenched & tempered |
| 4-5 | High-carbon steel, non-alloy (~0.75% C) | Springs, knives, hardened blades | SAE 1075 / 1080 / 1095 | DIN C75 / C100 W1 (1.1545) | BS EN 070 M 55, BW 1A | AFNOR XC75 | JIS SK3 / S58C | AS 1442 (high-carbon grades) | Hardened & tempered |
| 6-7 | Low-alloy steel (Cr-Mo), heat-treatable | Crankshafts, gears, high-tensile bolts, alloy steel general | SAE 4140 / AISI 4140 | DIN 42CrMo4 (1.7225) | BS EN 19, BS EN 708 M 40 | AFNOR 42CD4 | JIS SCM440 | AS 1444 4140 | Quenched & tempered |
| 8-9 | High-stress alloy steel (Ni-Cr-Mo) | Aircraft components, premium shafts, structural alloy | SAE 4340 / AISI 4340 | DIN 34CrNiMo6 (1.6582) | BS EN 24, BS 817 M 40 | AFNOR 35NCD6 | JIS SNCM 439 | AS 1444 4340 | Quenched & tempered (HT) |
| 10-11 | Tool steel — cold-work, air-hardening, HSS | Cold-work dies, punches, drill bits, taps, milling cutters | SAE D2, A2, O1, M2, M35, M42 | DIN X210Cr12 (1.2080, D3), X100CrMoV5-1 (1.2363, A2), S6-5-2 (1.3343, M2) | BS BD 3 (D3), BA 2 (A2), BM 2 (M2) | AFNOR Z200C12, Z85WDCV | JIS SKD 1 (D3), SKD 11 (D2), SKH 51 (M2) | AS 1239 (tool steel) | Hardened to working hardness |
| 12-13 | Corrosion-resistant martensitic / ferritic stainless | Cutlery, surgical, blade steel, mildly corrosive service | SAE/AISI 410 / 416 / 420 / 430 | DIN X12Cr13 (1.4006), X20Cr13 (1.4021), X12CrMoS17 (1.4104) | BS EN 410 S 21, 416 S 21, 420 S 45, 430 S 15 | AFNOR Z10C13 / Z20C13 | JIS SUS 410 / SUS 416 / SUS 420J2 / SUS 430 | AS 2837 410 / 420 / 430 | Annealed or hardened |
| 14.1 | Austenitic stainless — 304 / 18-8 | Food processing, indoor architectural, general industrial | SAE/AISI 304 / 304L / UNS S30400 | DIN X5CrNi18-10 (1.4301), X2CrNi19-11 (1.4307) | BS EN 304 S 15, 304 S 11 | AFNOR Z6CN18-09 / Z2CN18-10 | JIS SUS 304 / SUS 304L | AS 2837 304 / 304L | Annealed, slightly magnetic when cold-worked |
| 14.1 | Austenitic stainless — 316 / marine grade | Marine, coastal, food/pharma, chemical processing | SAE/AISI 316 / 316L / UNS S31600 | DIN X5CrNiMo17-12-2 (1.4401), X2CrNiMo17-12-2 (1.4404) | BS EN 316 S 31, 316 S 11 | AFNOR Z6CND17-11 / Z2CND17-12 | JIS SUS 316 / SUS 316L | AS 2837 316 / 316L | Annealed; A4 grade per ISO 3506 for fasteners |
| 14.2 | Duplex stainless — 2205 | Offshore, chemical plant, high-chloride service | SAE/AISI UNS S31803 / S32205 | DIN X2CrNiMoN22-5-3 (1.4462) | BS EN 1.4462 | AFNOR Z3CND22-05Az | JIS SUS 329J3L | AS 2837 S31803 | Annealed; PREN ~33-38 |
| 14.3 | Precipitation-hardening stainless — 17-4 PH | Aerospace components, valves, shafts requiring strength + corrosion | SAE/AISI UNS S17400 / 17-4 PH | DIN X5CrNiCuNb16-4 (1.4542) | BS EN 1.4542 | — | JIS SUS 630 | — | Solution-treated and age-hardened (H900-H1150) |
| 15-16 | Grey cast iron (GG) — ferritic / pearlitic | Engine blocks, machine bases, brake discs | SAE/AISI Class 30 / 35 / 40 (G3000 / G3500 / G4000) | DIN GG-25 (0.6025), GG-30 (0.6030) | BS Grade 250 / 300 (1452-1990) | AFNOR FGL 250 / 300 | JIS FC 250 / FC 300 | AS 1830 T260 / T300 | As-cast |
| 17-18 | Nodular / ductile cast iron (GGG) | Automotive crankshafts, machinery, ductile castings | SAE/AISI D 5506 / 60-40-18 / 80-55-06 | DIN GGG-50 (0.7050), GGG-60 (0.7060) | BS Grade 500-7 / 600-3 (2789-1985) | AFNOR FGS 500-7 | JIS FCD 500 / FCD 600 | AS 1831 500-7 / 600-3 | Annealed or normalised |
| 21-22 | Aluminium — wrought alloys (heat-treatable) | Structural extrusions, aerospace, automotive bodies | SAE/AISI 6061 / 2024 / 7075 | DIN AlMgSi1 (3.3211, 6061), AlCu4MgSi (3.1325, 2017) | BS L 86 (2017), L 87 (2024), 6061 | AFNOR A-G S, A-U2G2 | JIS A6061 / A2024 / A7075 | AS 1734 6061 / 2024 / 7075 | T6 / T651 temper typical |
| 23-24 | Aluminium — cast alloys | Engine blocks, transmission housings, manifolds | SAE/AISI 356.1 / 380 / A380 | DIN G-AlSi10Mg (3.2381, A356), GD-AlSi8Cu3 (3.2163, A380) | BS LM6 / LM25 / LM24 | AFNOR A-S10G | JIS AC4A / ADC10 / ADC12 | AS 1874 (cast Al alloys) | As-cast or heat-treated |
| 26-27 | Copper alloys — brass (CuZn) / bronze (CuSn) | Plumbing fittings, electrical, valves, decorative | SAE C 36000 / C 26000 / C 93200 / C 83600 | DIN CuZn36 (2.0335), CuZn39Pb3 (2.0401), G-CuSn7Zn4Pb (2.1090) | BS CZ 108 / CZ 121 (brass), LG 2 (bronze) | AFNOR U-Z36, U-E7Z5Pb4 | JIS C 2700 / C 3604 | AS 1567 C36000 (brass), AS 1565 (gunmetal) | Free-cutting / leaded grades available |
| 31-32 | Nickel alloys — Incoloy, Inconel base | High-temperature service, gas turbines, exhaust systems | SAE/AISI Incoloy 800 (UNS N08800), Inconel 600 (N06600), 625 (N06625) | DIN NiCr15Fe (2.4816), NiCr22Mo9Nb (2.4856) | BS NA 13 / 14 / 21 | AFNOR NC15Fe / NC22FeDNb | JIS NCF 600 / NCF 625 | — | Solution-treated |
| 33-34 | Inconel / Monel / Hastelloy higher-stress | Aerospace, chemical processing, severe corrosion + temperature | SAE/AISI Inconel 718 (N07718), Monel 400 (N04400), Hastelloy C-276 (N10276) | DIN NiCr19FeNbMo (2.4668), NiCu30Fe (2.4360) | — | AFNOR NC19FeNb | — | — | Age-hardened (Inconel) or annealed (Monel) |
| 36-37 | Titanium alloys | Aerospace, medical implants, marine, premium fastenings | SAE/AISI Grade 1-4 (CP-Ti), Grade 5 (Ti-6Al-4V, UNS R56400) | DIN Ti1 (3.7025), Ti6Al4V (3.7165) | BS TA 1 / TA 6 / TA 10 | AFNOR T-A6V | JIS Class 1-4 / Class 60 | — | Annealed; STA condition for highest strength |
| 38-41 | Hardened steel (≥45 HRC) and hardened tool steel | Hardened die surfaces, bearing races, knife edges, finishing operations | Variable — any P or M group hardened above 45 HRC | Variable — same as base material in hardened condition | — | — | — | — | Carbide tooling essential; HSS not viable |
ISO VDI 3323 — What It Is and Why It Matters
VDI 3323 is a standard published by the Verein Deutscher Ingenieure (Association of German Engineers — VDI) for testing cutting tool performance. Embedded within it is the material classification system used industry-wide for cutting parameter selection. The system groups materials by their machinability behaviour — how they respond to cutting tools — rather than by chemical composition alone. Two alloys with different chemistry but similar machinability fall in the same group; two alloys with similar chemistry but different heat treatment may fall in different groups.
Why the groups matter: cutting parameters (cutting speed Vc, feed rate) are recommended per material group, not per specific national-standard code. Knowing that AISI 4140 = Group 6-7 means you can look up appropriate speeds and feeds in any tool manufacturer's published cutting data — Sandvik, Kennametal, Mitsubishi, Iscar, OSG, Sutton, all reference the same VDI 3323 group numbers.
Australian Standards Layer — How AS/NZS Maps to International Codes
Australian industrial procurement frequently encounters all six major standards (AS/NZS, DIN, BS EN, AFNOR, JIS, SAE/AISI). The AS/NZS standards that cover the major material categories:
- AS 1442 — Carbon steels and carbon-manganese steels — hot-rolled bars, deformed bars and reinforcing rods. The correct standard for AS-spec carbon steel grades.
- AS 1444 — Wrought alloy steels — standard, hardenability (H) series, and engineering steels. Covers AS 1444 4140, AS 1444 4340 and the alloy steel range.
- AS 1239 — Tool steels (covers cold-work D series, air-hardening A series, and high-speed steel M/T series).
- AS 2837 — Wrought stainless steels for general engineering.
- AS 1830 / AS 1831 — Grey cast iron / spheroidal graphite (nodular ductile) cast iron.
- AS 1567 — Wrought copper alloys (brass and bronze).
- AS 1734 — Aluminium and aluminium alloys — wrought.
- AS 1874 — Aluminium and aluminium alloys — castings.
VERIFY current edition of each AS standard at standards.org.au before procurement-critical specification. Editions update periodically.
How to Use This Chart
- Identify your material by whichever national code appears on the certificate, drawing or supplier specification.
- Find the ISO VDI 3323 group from the table — this is your master reference for tooling selection.
- For procurement / sourcing equivalents internationally — use the cross-walk columns. Note: cross-references are nearest-equivalent, not exact. Chemistry typically matches within ±0.05% carbon and equivalent alloying; mechanical property tolerances vary between standards.
- For cutting parameters (Vc, feed rate) — use the ISO VDI group to look up in tool manufacturer cutting data. Australian-stocked tools (Sutton, Bordo, Seco) all reference this same system.
When Cross-References Are NOT Equivalent
Important caveats for safety-critical or regulatory work:
- Mechanical property tolerances differ even when chemistry matches. AS, DIN, ASTM/SAE and JIS all specify tensile strength, yield strength and elongation ranges — these don't always align exactly. For structural or pressure-vessel applications, specify the actual standard your design code requires.
- Heat treatment condition matters more than alloy chemistry. The same SAE 4140 supplied annealed (HB 197 max) vs quenched-and-tempered (HB 285-341) machines very differently. Always confirm supply condition.
- Trace element specifications differ. S, P, Pb content limits vary between national standards. Free-cutting variants (1140, 1144, 12L14) have intentionally higher sulphur/lead — different machinability, different mechanical properties.
- For critical applications, don't rely on cross-reference. Specify the exact standard your design code references.
Frequently Asked Questions
Q: What does ISO VDI 3323 mean?
ISO VDI 3323 is the international material classification system used for cutting tool selection. It groups materials by their machinability behaviour — how they respond to cutting — into around 41 groups. Most cutting tool manufacturers (Sandvik, Kennametal, Sutton, Iscar, OSG) publish their speeds and feeds data referenced to VDI 3323 group numbers.
Q: What's the Australian equivalent of SAE 4140?
AS 1444 4140. The chemistry (Cr-Mo low-alloy steel, ~0.40% C, 1% Cr, 0.2% Mo) is essentially identical to SAE 4140, DIN 42CrMo4, BS EN 19 and JIS SCM440. Mechanical property ranges in the heat-treated condition are also similar. For procurement, AS 1444 4140 is the correct AU national-standard reference.
Q: Is AISI 1045 the same as DIN C45?
Yes, equivalent. Both are non-alloy medium-carbon steel at approximately 0.45% C. AISI 1045 = SAE 1045 (US-AISI is the legacy of SAE), DIN C45 (1.0503) is the German equivalent. JIS S45C, BS EN 080 M 46 and AS 1442 K1045 are also equivalent. All sit in ISO VDI 3323 Group 2-3 for cutting purposes.
Q: What's 316 stainless called in Japan?
JIS SUS 316. The same austenitic stainless steel with 2-3% molybdenum that is called 316 in the US (SAE/AISI), X5CrNiMo17-12-2 in Germany (DIN 1.4401), and AS 2837 316 in Australia. For fasteners specifically, the ISO 3506 grade A4 covers the same material.
Q: How do I convert SAE alloy steel numbers to ISO/EN equivalents?
Cross-reference per the master table above. Common pairs: SAE 4140 ↔ DIN 42CrMo4 ↔ BS EN 19; SAE 4340 ↔ DIN 34CrNiMo6 ↔ BS EN 24; SAE 8620 ↔ DIN 21NiCrMo2 ↔ BS EN 805 M 20. The European DIN/EN system uses descriptive alloy codes (element + composition) whereas SAE/AISI uses a 4-digit category-based number.
Q: What does 'P-series' or 'M-series' mean in ISO material classification?
Letter prefixes group materials by family. ISO P = steels (groups 1-11). ISO M = stainless steels (groups 12-14). ISO K = cast iron (groups 15-20). ISO N = non-ferrous (aluminium, magnesium, copper — groups 21-28). ISO S = super alloys (nickel-base, titanium, etc. — groups 31-37). ISO H = hardened materials above 45 HRC (groups 38-41). This is a different classification axis to VDI 3323 numbers — the ISO letter and the VDI number both appear in tool manufacturer cutting data.
Q: What is AS 1442 vs AS 1444 — what's the difference?
AS 1442 covers carbon steels — hot-rolled bars, deformed bars, reinforcing rods. AS 1444 covers wrought alloy steels — heat-treatable engineering steels including 4140, 4340 and the standard hardenability-series alloy grades. AS 1442 = 'plain carbon'; AS 1444 = 'alloy'. Don't confuse — AS 1442 is the correct reference for carbon steel grades, AS 1444 for alloy steels.
Q: What standard covers Australian stainless steel grades?
AS 2837 — Wrought stainless steels for general engineering — covers the major austenitic (304, 316), martensitic (410, 420, 430), and duplex grades. For fasteners specifically, ISO 3506-1 and ISO 3506-2 are directly applicable in Australia (there is no AS-specific stainless fastener standard).
Q: Are SAE and AISI numbers the same?
Effectively yes. AISI (American Iron and Steel Institute) historically published the numbering system; SAE (Society of Automotive Engineers) adopted and maintained it. Today the SAE J403 (carbon steels) and SAE J404 (alloy steels) standards are the active references — AISI numbers and SAE numbers for the same alloy are identical. UNS (Unified Numbering System) is a more comprehensive identifier maintained by SAE + ASTM.
Q: What's the difference between cast iron grades GG-25 and GGG-50?
GG-25 is grey cast iron (German notation for grauguss / grey cast) with minimum 250 N/mm² tensile strength. GGG-50 is spheroidal graphite (nodular ductile) iron — the graphite forms spheres rather than flakes, giving significantly higher tensile strength (500 N/mm²) and elongation. GGG/ductile iron is the modern standard for highly-stressed cast components like crankshafts; grey iron remains common for vibration-damping applications like engine blocks and machine bases.
Q: Why are there so many ways to describe the same material?
Different national standards bodies developed independently — SAE/AISI in the US, DIN in Germany, BSI in the UK, AFNOR in France, JIS in Japan, Standards Australia in Australia. Each evolved their own naming convention and tolerance system. Modern alignment is happening via ISO standards (ISO 683 for engineering steels, ISO 6892 for tensile testing) but national codes persist on certificates, drawings and procurement specifications worldwide.
Related AIMS Engineering Reference Guides
- Steel Grades Comparison — Carbon, Alloy, Tool Steel (companion sibling)
- Stainless Steel Fastener Grades: A2, A4, -70 & -80
- Hardness Testing & Conversion Reference
- Material Density Reference Chart
- Drill Bit Metric / Imperial Size Chart
- Bolt Grade Chart — Carbon Steel Property Classes
AIMS Engineering Materials Range
AIMS Industrial stocks raw materials and cutting tools across the major material groups. For tooling matched to specific workpiece materials, browse our Sutton Tools range (Australian-made HSS, cobalt and carbide cutting tools), or contact our technical team for material-specific tooling recommendations.
Need help matching the right cutting tool to a tricky material — particularly hardened steels, austenitic stainless, titanium or super alloys? Contact AIMS on (02) 9773 0122 — we'll match the tool material, coating and cutting parameters to your application.