--- title: "GB steel grades — 1318 designations — Page 19" description: "Steel grades designated under GB, with chemical composition, mechanical properties and equivalents in other standards. 1318 designations across 991…" canonical: https://steelequivalents.com/materials/gb/page/19 language: en robots: index, follow og_type: website type: material-standard language_alternates: en: https://steelequivalents.com/materials/gb/page/19.md cs: https://steelequivalents.com/cs/materiály/gb.md de: https://steelequivalents.com/de/werkstoffe/gb.md es: https://steelequivalents.com/es/materiales/gb.md fr: https://steelequivalents.com/fr/matériaux/gb.md hu: https://steelequivalents.com/hu/anyagok/gb.md it: https://steelequivalents.com/it/materiali/gb.md nl: https://steelequivalents.com/nl/materialen/gb.md pl: https://steelequivalents.com/pl/materiały/gb.md pt: https://steelequivalents.com/pt/materiais/gb.md ru: https://steelequivalents.com/ru/материалы/gb.md tr: https://steelequivalents.com/tr/malzemeler/gb.md zh: https://steelequivalents.com/zh/材料/gb.md ja: https://steelequivalents.com/ja/材料/gb.md ar: https://steelequivalents.com/ar/المواد/gb.md ko: https://steelequivalents.com/ko/재료/gb.md pt-br: https://steelequivalents.com/pt-br/materiais/gb.md hi: https://steelequivalents.com/hi/सामग्री/gb.md content_hash: sha256:1c31500ade909cc076448b9523c26d0f089b8ad8d15bb22144b2e6adc7dcda7e generated: 2026-09-22 --- > **Machine-readable Markdown rendering.** This is a Markdown representation of a web page, > served for AI agents and crawlers as a token-efficient alternative to the full HTML. > Full interactive HTML version: https://steelequivalents.com/materials/gb/page/19 > Canonical URL: https://steelequivalents.com/materials/gb/page/19 > Available languages: en, cs, de, es, fr, hu, it, nl, pl, pt, ru, tr, zh, ja, ar, ko, pt-br, hi > Change detection: `content_hash` is the SHA-256 of this document's Markdown body — everything > below this block, whitespace-trimmed, excluding the front-matter. Compare it to detect a real > content change; `generated` moves on every render and is not a change signal. GB · 1,318 grades # GB steel grades — 1318 designations — Page 19 Every grade designated under GB, with the material number it maps to, what kind of steel it is, its carbon window and how many other standards carry it. Open a grade for its full composition, properties and its designations in other standards. Unless marked, every name here is an indicative cross-reference, not an asserted identity — the grades are close, not interchangeable. 22 of 50 rows differ and carry a “This grade’s own name” mark. ## Also known as 1318 designations | Grade | Material no. | Category | C% by weight | Also in other standards | |---|---|---|---|---| | [ML25B](/materials/gb/ml25b "ML25B") This grade’s own name | — | — | 0.23–0.28 | — | | [ML25CrMo](/materials/gb/ml25crmo "ML25CrMo") This grade’s own name | — | — | 0.23–0.28 | 3 | | [ML25Mn](/materials/gb/ml25mn "ML25Mn") | [1.0528](/materials/material-no/1.0528 "1.0528") | Quenched and tempered steels | 0.27–0.34 | 14 | | [ML25MnB](/materials/gb/ml25mnb "ML25MnB") This grade’s own name | — | — | 0.23–0.28 | — | | [ML28B](/materials/gb/ml28b "ML28B") This grade’s own name | — | — | 0.25–0.32 | — | | [ML30](/materials/gb/ml30 "ML30") | [1.0528](/materials/material-no/1.0528 "1.0528") | Quenched and tempered steels | 0.27–0.34 | 14 | | [ML30B](/materials/gb/ml30b "ML30B") This grade’s own name | — | — | 0.28–0.33 | — | | [ML30Cr](/materials/gb/ml30cr "ML30Cr") This grade’s own name | — | — | 0.28–0.33 | — | | [ML30Cr13](/materials/gb/ml30cr13 "ML30Cr13") This grade’s own name | — | — | 0.26–0.35 | — | | [ML30CrMo](/materials/gb/ml30crmo "ML30CrMo") | [1.7220](/materials/material-no/1.7220 "1.7220") | Quenched and tempered steels | 0.3–0.37 | 24 | | [ML30CrMo](/materials/gb/ml30crmo "ML30CrMo") | [1.7218](/materials/material-no/1.7218 "1.7218") | Quenched and tempered steels | 0.22–0.29 | 25 | | [ML30CrMoA](/materials/gb/ml30crmoa "ML30CrMoA") | [1.7220](/materials/material-no/1.7220 "1.7220") | Quenched and tempered steels | 0.3–0.37 | 24 | | [ML30CrMoA](/materials/gb/ml30crmoa "ML30CrMoA") | [1.7218](/materials/material-no/1.7218 "1.7218") | Quenched and tempered steels | 0.22–0.29 | 25 | | [ML30Mn](/materials/gb/ml30mn "ML30Mn") | [1.1170](/materials/material-no/1.1170 "1.1170") | Quenched and tempered steels | 0.25–0.32 | 16 | | [ML30MnB](/materials/gb/ml30mnb "ML30MnB") This grade’s own name | — | — | 0.28–0.33 | — | | [ML35](/materials/gb/ml35 "ML35") | [1.0501](/materials/material-no/1.0501 "1.0501") | Quenched and tempered steels | 0.32–0.39 | 23 | | [ML35B](/materials/gb/ml35b "ML35B") This grade’s own name | — | — | 0.33–0.38 | — | | [ML35Cr](/materials/gb/ml35cr "ML35Cr") This grade’s own name | — | — | 0.33–0.38 | 4 | | [ML35CrMo](/materials/gb/ml35crmo "ML35CrMo") | [1.7220](/materials/material-no/1.7220 "1.7220") | Quenched and tempered steels | 0.3–0.37 | 24 | | [ML35MnB](/materials/gb/ml35mnb "ML35MnB") This grade’s own name | — | — | 0.33–0.38 | — | | [ML37Cr](/materials/gb/ml37cr "ML37Cr") This grade’s own name | — | — | 0.34–0.41 | — | | [ML37CrB](/materials/gb/ml37crb "ML37CrB") This grade’s own name | — | — | 0.34–0.41 | — | | [ML38CrA](/materials/gb/ml38cra "ML38CrA") | [1.7034](/materials/material-no/1.7034 "1.7034") | Quenched and tempered steels | 0.34–0.41 | 23 | | [ML40](/materials/gb/ml40 "ML40") | [1.0511](/materials/material-no/1.0511 "1.0511") | Quenched and tempered steels | 0.37–0.44 | 21 | | [ML40Cr](/materials/gb/ml40cr "ML40Cr") | [1.7034](/materials/material-no/1.7034 "1.7034") | Quenched and tempered steels | 0.34–0.41 | 23 | | [ML40CrMo](/materials/gb/ml40crmo "ML40CrMo") This grade’s own name | — | — | 0.38–0.43 | 4 | | [ML40CrNiMoA](/materials/gb/ml40crnimoa "ML40CrNiMoA") | [1.6565](/materials/material-no/1.6565 "1.6565") | Quenched and tempered steels | 0.35–0.45 | 15 | | [ML40MnB](/materials/gb/ml40mnb "ML40MnB") This grade’s own name | — | — | 0.38–0.43 | — | | [ML42CrMo](/materials/gb/ml42crmo "ML42CrMo") This grade’s own name | — | — | 0.38–0.45 | 4 | | [ML45](/materials/gb/ml45 "ML45") | [1.0503](/materials/material-no/1.0503 "1.0503") | Quenched and tempered steels | 0.42–0.5 | 24 | | [ML45Cr](/materials/gb/ml45cr "ML45Cr") This grade’s own name | — | — | 0.43–0.48 | 2 | | [ML45CrMo](/materials/gb/ml45crmo "ML45CrMo") This grade’s own name | — | — | 0.43–0.48 | 2 | | [ML45Mn](/materials/gb/ml45mn "ML45Mn") | [1.0912](/materials/material-no/1.0912 "1.0912") | Others | 0.42–0.5 | 11 | | [MnCrWV](/materials/gb/mncrwv "MnCrWV") This grade’s own name | — | — | 0.9–1.05 | — | | [N029](/materials/gb/n029 "N029") | [1.3243](/materials/material-no/1.3243 "1.3243") | High-speed steels | 0.87–0.95 | 19 | | [Ni25Cr15Ti2MoMn](/materials/gb/ni25cr15ti2momn "Ni25Cr15Ti2MoMn") This grade’s own name | — | — | ≤ 0.08 | — | | [NiFe36Cr12Mo6Ti3](/materials/gb/nife36cr12mo6ti3 "NiFe36Cr12Mo6Ti3") | [2.4975](/materials/material-no/2.4975 "2.4975") | High-temperature steels | ≤ 0.1 | 4 | | [NM400](/materials/gb/nm400 "NM400") This grade’s own name | — | — | ≤ 0.3 | — | | [NM500](/materials/gb/nm500 "NM500") This grade’s own name | — | — | ≤ 0.38 | — | | [NS1403](/materials/gb/ns1403 "NS1403") | [2.4660](/materials/material-no/2.4660 "2.4660") | Nickel and cobalt alloys | ≤ 0.07 | 4 | | [NS1403](/materials/gb/ns1403 "NS1403") | [1.4527](/materials/material-no/1.4527 "1.4527") | Others | ≤ 0.06 | 3 | | [NS1502](/materials/gb/ns1502 "NS1502") | [2.4854](/materials/material-no/2.4854 "2.4854") | Others | ≤ 0.05 | 1 | | [NS3103](/materials/gb/ns3103 "NS3103") | [2.4851](/materials/material-no/2.4851 "2.4851") | Heat resistant steels | 0.03–0.1 | 7 | | [NS3305](/materials/gb/ns3305 "NS3305") | [2.4610](/materials/material-no/2.4610 "2.4610") | Nickel and cobalt alloys | ≤ 0.015 | 3 | | [NS3308](/materials/gb/ns3308 "NS3308") | [2.4602](/materials/material-no/2.4602 "2.4602") | Nickel and cobalt alloys | ≤ 0.01 | 5 | | [NS3309](/materials/gb/ns3309 "NS3309") | [2.4606](/materials/material-no/2.4606 "2.4606") | Others | ≤ 0.01 | 3 | | [NS3312](/materials/gb/ns3312 "NS3312") | [2.4665](/materials/material-no/2.4665 "2.4665") | High-temperature steels | 0.05–0.15 | 11 | | [NS3313](/materials/gb/ns3313 "NS3313") | [2.4733](/materials/material-no/2.4733 "2.4733") | Others | 0.05–0.15 | 5 | | [NS3402](/materials/gb/ns3402 "NS3402") | [2.4663](/materials/material-no/2.4663 "2.4663") | Nickel and cobalt alloys | 0.05–0.1 | 6 | | [NS5200](/materials/gb/ns5200 "NS5200") | [2.4066](/materials/material-no/2.4066 "2.4066") | Nickel and cobalt alloys | ≤ 0.1 | 10 | **This grade’s own name** — recorded in our sources as this grade’s own designation under that standard. **Indicative** — taken from a published cross-reference table; a close match, not a guarantee of interchangeability. Verify against the mill certificate before ordering. **Withdrawn** — designation no longer current — a separate column from the two above, so a name can be same grade and withdrawn at once. [Previous](/materials/gb/page/18 "Previous") Page 19 of 27[Next](/materials/gb/page/20 "Next")