SS 321 Mirror No.8 Finish SheetASTM A240 · ASTM A480 (No.8) · Manufacturer, trader & exporter, India
AISI 321 · UNS S32100
An SS 321 mirror no.8 finish sheet is sheet polished to a mirror surface, made from SS 321 to ASTM A240. No.8 mirror is polished and buffed for signage, décor and cleanroom surfaces.
- ASTM A240
- ASTM A480 (No.8)
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an SS 321 Mirror No.8 Finish Sheet?
- What it is
- Sheet polished to a mirror surface
- Material
- ASTM A240
- Dimensions
- ASTM A480 (No.8)
- Grade
- SS 321 · UNS S32100
- Best at
- High-temperature service between 425 and 815 °C
SS 321 Mirror No.8 Finish Sheet Specification
| Product | SS 321 Mirror No.8 Finish Sheet |
|---|---|
| Material standard | ASTM A240 |
| Dimensional standard | ASTM A480 (No.8) |
| Thickness | Below 4.76 mm (3/16") |
| Size | 1000 / 1219 / 1250 / 1500 × 2000 / 2438 / 2500 / 3000 mm or cut |
| Testing | PMI (as specified in the PO) · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 or 3.2 on request / as specified in the PO |
When to Choose a Mirror No.8 Finish Sheet
No.8 mirror is polished and buffed for signage, décor and cleanroom surfaces.
- True mirror
- Polished and buffed
- Laser-film protected
More on choosing: Mirror No.8 finish sheet guide.
SS 321 Mirror No.8 Finish Sheet: Why 321 for mirror no.8 finish sheets
No.8 mirror is polished and buffed for signage, décor and cleanroom surfaces. In SS 321, the choice usually comes down to the medium and temperature — the rows here are the points buyers check for this exact combination.
| Why this grade | Stainless sheet is formed and finished for visible or hygienic surfaces. SS 321 is picked for high-temperature service between 425 and 815 °C. |
|---|---|
| Typical service | Aircraft exhaust — Manifolds, bellows and exhaust systems. |
| Matching filler | ER347 (AWS A5.9) |
SS 321 Mirror No.8 Finish Sheet Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Chromium | As specified |
| Nickel | As specified |
| Titanium | As specified |
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Nitrogen | As specified |
| Phosphorus | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM A240 for UNS S32100.
SS 321 Mirror No.8 Finish Sheet Mechanical Properties
Under technical review for TDS.
| Property | Current requirement |
|---|---|
| Tensile strength | As specified |
| Yield strength 0.2% | As specified |
| Elongation | As specified |
| Hardness | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification and condition to be verified: ASTM A240 for UNS S32100 — Annealed plate & sheet.
Full chemistry, properties and equivalents are on the SS 321 grade page.
Other SS 321 sheets
SS 321 Mirror No.8 Finish Sheet — questions buyers ask
How is mirror finish protected?
With a laser-grade PVC film that stays on until installation.
Which standard covers SS 321 mirror no.8 finish sheets?
The material is ASTM A240; dimensions follow ASTM A480 (No.8). Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a SS 321 mirror no.8 finish sheet?
The alloy price, the size and dimensions, quantity, and the testing and documents required. Send your list and we quote the same working day.
What documents do you supply?
EN 10204 3.1 or 3.2 certificates available on request / as specified in the PO; dimensional reports as required. PMI can be arranged depending on product and requirements, as specified in the PO.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026