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2B · BA · No.4 · 表面 · 验收
2B / BA / No.4 Finishes: From Process to Acceptance
2B is the general-purpose finish produced by cold rolling, annealing, pickling and skin pass; BA is bright annealing, giving a brighter, smoother surface; No.4 is a brushed finish. Acceptance should specify finish grade, roughness and permitted defects.
2B: After cold rolling, the strip is annealed, pickled and skin-passed, giving a uniform matte surface. It is the most commonly used grade and is suitable for general deep drawing, kitchenware and industrial parts.
BA: Bright annealing under a protective atmosphere produces a bright surface with uniform reflectivity, suitable for appliance panels, decorative applications and subsequent coating.
No.4: Abrasive brushing creates short, straight lines; suitable for elevators, architectural decoration and kitchen countertops. The grain direction and roughness must be agreed.
Acceptance recommendations: 1) Specify the standard (e.g. ASTM A480 / EN 10051) and the finish designation; 2) agree on the roughness Ra and gloss range; 3) agree on permitted defects (scratches, roll marks, color difference, oxidation tint) and the limits for grinding repair; 4) for BA surfaces, pay particular attention to the protective film and transport scratches.
Compiled by SteelWe editors and industry experts. For industry exchange only; not trading or investment advice. Cite the source when quoting.