--- title: "A193 Grade B8S — composition, equivalents and standards" description: "A193 Grade B8S is a designation in ASTM for the grade also listed as S21800. Designations recorded for this grade: 21." canonical: https://steelequivalents.com/materials/astm/a193-grade-b8s language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/astm/a193-grade-b8s.md cs: https://steelequivalents.com/cs/materiály/astm/a193-grade-b8s.md de: https://steelequivalents.com/de/werkstoffe/astm/a193-grade-b8s.md es: https://steelequivalents.com/es/materiales/astm/a193-grade-b8s.md fr: https://steelequivalents.com/fr/matériaux/astm/a193-grade-b8s.md hu: https://steelequivalents.com/hu/anyagok/astm/a193-grade-b8s.md it: https://steelequivalents.com/it/materiali/astm/a193-grade-b8s.md nl: https://steelequivalents.com/nl/materialen/astm/a193-grade-b8s.md pl: https://steelequivalents.com/pl/materiały/astm/a193-grade-b8s.md pt: https://steelequivalents.com/pt/materiais/astm/a193-grade-b8s.md ru: https://steelequivalents.com/ru/материалы/astm/a193-grade-b8s.md tr: https://steelequivalents.com/tr/malzemeler/astm/a193-grade-b8s.md zh: https://steelequivalents.com/zh/材料/astm/a193-grade-b8s.md ja: https://steelequivalents.com/ja/材料/astm/a193-grade-b8s.md ar: https://steelequivalents.com/ar/المواد/astm/a193-grade-b8s.md ko: https://steelequivalents.com/ko/재료/astm/a193-grade-b8s.md pt-br: https://steelequivalents.com/pt-br/materiais/astm/a193-grade-b8s.md hi: https://steelequivalents.com/hi/सामग्री/astm/a193-grade-b8s.md content_hash: sha256:1a75c5c9a5e39d7091a583089aa9f14f60f6dbf15f4c378428b9ba3b02741a42 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/astm/a193-grade-b8s > Canonical URL: https://steelequivalents.com/materials/astm/a193-grade-b8s > 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. ASTM · United States · 21 designations # A193 Grade B8S A193 Grade B8S is a designation in ASTM for the grade also listed as S21800. We list 21 designations recorded for this grade, in the standards UNS, AISI / SAE, ASTM and SAE AMS. - *Designations* **21** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=d37f03e2-a273-4ff7-a26d-a4a0d8de99fd&designation=a48c9df6-9234-4d25-a4f8-893aa48578b3 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/astm/a193-grade-b8s.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [UNS S21800 This grade’s own name](/materials/uns/s21800 "UNS S21800") ## Also known as 21 designations · 4 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. UNS United States · 2 - [S21800 This grade’s own name](/materials/uns/s21800 "UNS S21800") - [S41623 Indicative](/materials/uns/s41623 "UNS S41623") AISI / SAE United States · 2 - [416Se Indicative](/materials/aisi-sae/416se "AISI / SAE 416Se") - [51416Se Indicative](/materials/aisi-sae/51416se "AISI / SAE 51416Se") ASTM United States · 15 - **A193 Grade B8S Indicative** - [A194 Indicative](/materials/astm/a194 "ASTM A194") - [A240 Indicative](/materials/astm/a240 "ASTM A240") - [A276 Indicative](/materials/astm/a276 "ASTM A276") - [A314 Indicative](/materials/astm/a314 "ASTM A314") - [A473 Indicative](/materials/astm/a473 "ASTM A473") - [A479 Indicative](/materials/astm/a479 "ASTM A479") - [A511 Indicative](/materials/astm/a511 "ASTM A511") - [A581 Indicative](/materials/astm/a581 "ASTM A581") - [A582 Indicative](/materials/astm/a582 "ASTM A582") - [A895 Indicative](/materials/astm/a895 "ASTM A895") - [F593 Indicative](/materials/astm/f593 "ASTM F593") - [F594 Indicative](/materials/astm/f594 "ASTM F594") - [F738 Indicative](/materials/astm/f738 "ASTM F738") - [F836 Indicative](/materials/astm/f836 "ASTM F836") SAE AMS United States / Aerospace · 2 - [5610 Indicative](/materials/ams/5610 "SAE AMS 5610") - [5848 Indicative bar forging wire](/materials/ams/5848 "SAE AMS 5848") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Predicted transformation temperatures Not enough recorded composition to predict a transformation temperature for this grade — missing: C, Mn, Si, 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. ## 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=d37f03e2-a273-4ff7-a26d-a4a0d8de99fd&designation=a48c9df6-9234-4d25-a4f8-893aa48578b3 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/astm/a193-grade-b8s.pdf "Datasheet as PDF")