--- title: "STH660 — composition, equivalents and standards" description: "STH660: 1 equivalent designations across 1 standards, with the recorded chemical composition shown next to the source text." canonical: https://steelequivalents.com/materials/ks/sth660 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/ks/sth660.md cs: https://steelequivalents.com/cs/materiály/ks/sth660.md de: https://steelequivalents.com/de/werkstoffe/ks/sth660.md es: https://steelequivalents.com/es/materiales/ks/sth660.md fr: https://steelequivalents.com/fr/matériaux/ks/sth660.md hu: https://steelequivalents.com/hu/anyagok/ks/sth660.md it: https://steelequivalents.com/it/materiali/ks/sth660.md nl: https://steelequivalents.com/nl/materialen/ks/sth660.md pl: https://steelequivalents.com/pl/materiały/ks/sth660.md pt: https://steelequivalents.com/pt/materiais/ks/sth660.md ru: https://steelequivalents.com/ru/материалы/ks/sth660.md tr: https://steelequivalents.com/tr/malzemeler/ks/sth660.md zh: https://steelequivalents.com/zh/材料/ks/sth660.md ja: https://steelequivalents.com/ja/材料/ks/sth660.md ar: https://steelequivalents.com/ar/المواد/ks/sth660.md ko: https://steelequivalents.com/ko/재료/ks/sth660.md pt-br: https://steelequivalents.com/pt-br/materiais/ks/sth660.md hi: https://steelequivalents.com/hi/सामग्री/ks/sth660.md content_hash: sha256:025f549ae49f11934635d498059e92ed750d62a0f510cc300a9f6e573da6b49e generated: 2026-09-24 --- > **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/ks/sth660 > Canonical URL: https://steelequivalents.com/materials/ks/sth660 > 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. KS · South Korea · 1 designation # STH660 STH660 is a grade designated under KS. Its recorded composition includes C ≤ 0.08%, Ti 1.9–2.35%, Cr 13.5–16%, Mn ≤ 2% and Ni 24–27%. No cross-standard equivalents are recorded for this grade yet. - *Designations* **1** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=c4f8d588-024d-460d-9d28-6ec2ba9a435d&designation=280cc945-95d8-4b3d-9155-47a95cafa7c8 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/ks/sth660.pdf "Datasheet as PDF") ## Chemical composition 12 elements on file · weight % What this alloy is Fe Ni Cr Ti Iron — the balance, never listed by a standard — 52.6 % Ni — 25.5 % Cr — 14.8 % Ti — 2.1 % Traces & impurities · 5.1 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.08 | | Si | ≤ 1 | | Mn | ≤ 2 | | P | ≤ 0.04 | | S | ≤ 0.03 | | Cr | 13.5–16 | | Mo | 1–1.5 | | Ni | 24–27 | | V | 0.1–0.5 | | Al | ≤ 0.35 | | Ti | 1.9–2.35 | | B | 0.001–0.01 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Molybdenum Nickel Vanadium Aluminium Titanium Boron 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 | |---|---|---|---|---| | B | 0.001 - 0.01 | 0.001 | 0.010 | Range | | C | max 0.08 | — | 0.080 | Max | | Al | max 0.35 | — | 0.350 | Max | | Si | max 1 | — | 1.000 | Max | | P | max 0.04 | — | 0.040 | Max | | S | max 0.03 | — | 0.030 | Max | | Ti | 1.9 - 2.35 | 1.900 | 2.350 | Range | | V | 0.1 - 0.5 | 0.100 | 0.500 | Range | | Cr | 13.5 - 16 | 13.500 | 16.000 | Range | | Mn | max 2 | — | 2.000 | Max | | Ni | 24 - 27 | 24.000 | 27.000 | Range | | Mo | 1 - 1.5 | 1.000 | 1.500 | Range | 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 This grade's composition falls outside the published model's validated range (a low-alloy composition window), so no transformation temperature is predicted here. ## 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. ## 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=c4f8d588-024d-460d-9d28-6ec2ba9a435d&designation=280cc945-95d8-4b3d-9155-47a95cafa7c8 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/ks/sth660.pdf "Datasheet as PDF")