ASTM A480
Standard Specification for General Requirements for Flat-Rolled Stainless and Heat-Resisting Steel Plate, Sheet, and Strip
Provides general requirements and standard finish designations for flat-rolled stainless and heat-resisting steel plate, sheet, and strip.
What ASTM A480 specifies
ASTM A480 is the general-requirements specification behind many stainless flat-product orders and defines commonly requested mill and mechanically finished appearances. No. 1 is hot-rolled, annealed, and descaled; 2D is cold-rolled with a dull finish; 2B adds a light final cold roll for a smoother reflective finish; and BA is bright annealed. No. 3 and No. 4 are directional polished finishes, while No. 6, No. 7, and No. 8 represent progressively smoother and more reflective buffed or polished appearances. Finish designations control process and visual character, not one universal Ra value. Samples should govern critical cosmetic work.
ASTM A480 types and classes
Every designation the document defines, with the thickness it requires and the tests it imposes.
| Designation | Meaning | Requirement / test |
|---|---|---|
No. 1 | Hot rolled, annealed, and descaled | Visual finish and product requirements |
2D | Cold rolled, annealed, descaled, with a dull finish | Visual finish and product requirements |
2B | Cold rolled, annealed, descaled, and lightly cold rolled for a smooth moderately reflective finish | Visual finish and product requirements |
BA | Cold rolled and bright annealed to retain a smooth reflective surface | Visual finish and product requirements |
No. 3 | Intermediate directional polished finish | Visual comparison and agreed sample |
No. 4 | General-purpose directional polished finish | Visual comparison and agreed sample |
No. 6 | Dull satin finish produced from a finer polished base and buffing | Visual comparison and agreed sample |
No. 7 | High-reflectivity finish retaining some polishing lines | Visual comparison and agreed sample |
No. 8 | Highly reflective mirror finish with polishing lines substantially removed | Visual comparison and agreed sample |
Tests and the drawing call-out
Tests the document imposes
- Visual finish examination
- Dimensional and flatness requirements
- Mechanical and chemical requirements from the applicable product specification
How to cite it
Drawing call-out
STAINLESS SHEET FINISH PER ASTM A480, <NO. 1|2D|2B|BA|NO. 3|NO. 4|NO. 6|NO. 7|NO. 8>; DIRECTION <IF APPLICABLE>Angle brackets mark the choices the drawing must make; every finish page shows a completed example.
ASTM A480 — frequently asked
What is a 2B stainless finish?
2B is cold rolled, annealed, descaled, and lightly cold rolled. It is smooth and moderately reflective but is not a mirror polish.
What is the difference between No. 4 and No. 8 stainless finish?
No. 4 is a directional general-purpose polish with visible grain. No. 8 is a highly reflective mirror finish with polishing lines substantially removed.
Does ASTM A480 assign an Ra to each finish?
No single universal Ra defines these appearance designations. For critical work, state roughness separately and approve a directional sample.
ASTM A480 is copyrighted by ASTM International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗