--- title: "SWOSM — Spring steels" description: "SWOSM: 2 equivalent designations across 2 standards, with the recorded chemical composition shown next to the source text." canonical: https://steelequivalents.com/materials/jis/swosm language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/jis/swosm.md cs: https://steelequivalents.com/cs/materiály/jis/swosm.md de: https://steelequivalents.com/de/werkstoffe/jis/swosm.md es: https://steelequivalents.com/es/materiales/jis/swosm.md fr: https://steelequivalents.com/fr/matériaux/jis/swosm.md hu: https://steelequivalents.com/hu/anyagok/jis/swosm.md it: https://steelequivalents.com/it/materiali/jis/swosm.md nl: https://steelequivalents.com/nl/materialen/jis/swosm.md pl: https://steelequivalents.com/pl/materiały/jis/swosm.md pt: https://steelequivalents.com/pt/materiais/jis/swosm.md ru: https://steelequivalents.com/ru/материалы/jis/swosm.md tr: https://steelequivalents.com/tr/malzemeler/jis/swosm.md zh: https://steelequivalents.com/zh/材料/jis/swosm.md ja: https://steelequivalents.com/ja/材料/jis/swosm.md ar: https://steelequivalents.com/ar/المواد/jis/swosm.md ko: https://steelequivalents.com/ko/재료/jis/swosm.md pt-br: https://steelequivalents.com/pt-br/materiais/jis/swosm.md hi: https://steelequivalents.com/hi/सामग्री/jis/swosm.md content_hash: sha256:6511af64c3859bc2b902b72974892f91b8b727d81d2614bd63744b054ce19694 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/jis/swosm > Canonical URL: https://steelequivalents.com/materials/jis/swosm > 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. JIS · Japan · 2 designations # SWOSM SWOSM is a material in the category [Spring steels](/categories/spring-steels "Spring steels"). Its recorded composition includes C 0.56–0.64%, Si 1.5–1.8%, P ≤ 0.035%, Mn 0.7–1% and Cu ≤ 0.3%. We list one designation recorded for this grade, in the standard KS. Recorded mechanical properties include Rm 1370–1810 N/mm². - [*Category* **Spring steels · 52 grades**](/categories/spring-steels "Category: Spring steels · 52 grades") - *Designations* **2** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=50a79078-0111-43f0-a42f-ec9ea4f1340e&designation=40b7fff1-35ac-4b44-adad-3e350e83a96d "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/jis/swosm.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - **KS SWOSM This grade’s own name** ## About Spring steels Spring steels are alloy steels designed to store and release elastic energy repeatedly without permanent deformation. They are characterised by a combination of strength, hardness and resilience, making them suitable for springs, clips, washers and other components subjected to repeated flexing or shock. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 2 designations · 2 standards · nothing hidden 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. JIS Japan · 1 - **SWOSM This grade’s own name** KS South Korea · 1 - **SWOSM This grade’s own name** Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 6 elements on file · weight % What this alloy is Fe Si Mn C Iron — the balance, never listed by a standard — 96.5 % Si — 1.7 % Mn — 0.9 % C — 0.6 % Traces & impurities · 0.4 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.56–0.64 | | Si | 1.5–1.8 | | Mn | 0.7–1 | | P | ≤ 0.035 | | S | ≤ 0.035 | | Cu | ≤ 0.3 | Carbon Silicon Manganese Phosphorus Sulfur Copper 0.01 % 0.1 % 1 % 10 % 100 % The scale is logarithmic, not the element’s raw share of the alloy — the only honest way to fit 0.01 % and 100 % in one picture, and it means every value here can be compared with every other. | Element | As published source text, verbatim | Min% by weight | Max% by weight | Bound | |---|---|---|---|---| | C | 0.56 - 0.64 | 0.560 | 0.640 | Range | | Si | 1.5 - 1.8 | 1.500 | 1.800 | Range | | P | max 0.035 | — | 0.035 | Max | | S | max 0.035 | — | 0.035 | Max | | Mn | 0.7 - 1 | 0.700 | 1.000 | Range | | Cu | max 0.3 | — | 0.300 | Max | The published column is the source string byte-for-byte, decimal comma and all; Min and Max are the parsed bounds. Elements not listed have no value on file — they are omitted, never inferred. ## Predicted transformation temperatures Not enough recorded composition to predict a transformation temperature for this grade — missing: Ni, Cr, Mo. ## Physical & mechanical properties An absent property means we hold no value for it — it is left out rather than estimated, interpolated from a neighbouring grade, or filled from a handbook. It does not mean the property is undefined for the material. ## Properties by condition 1 conditions · 1 values By delivery state**no delivery state stated** source `steelks` | Delivery state | Rm N/mm² | |---|---| | Wires | 1370 – 1810 | Every figure holds only for the condition on its own row. Values are never merged across conditions or across sources, never averaged, and never interpolated between two rows. An em dash means no value on file — never zero. Figures are converted to the unit in the column header; the source’s own wording is kept and shown where the two differ. ## Looking for this grade under another name? Search the catalogue by designation, material number or composition — every name on this page is itself a way in. [Search](/search "Steel grade search")[Inquiry](/inquiry?material=50a79078-0111-43f0-a42f-ec9ea4f1340e&designation=40b7fff1-35ac-4b44-adad-3e350e83a96d "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/jis/swosm.pdf "Datasheet as PDF")