Surface Finish as Cast
General purpose of standard on as cast surface finish. For some applications it is desirable to specifiy finish requirements. Specification is to classify as cast surface finish of diecastings into a series of grades so that the type of finish required may be defined in advance.
Cast Finish
- Surface imperfections (cold shut, blisters, oil flow marks, surface porosity, etc.) not objectionable.
- Some surface imperfections (cold shut, rubs, surface porosity, etc.) not objectionable.
- Slight surface imperfections (cold shut, rubs, surface porosity, etc.), that can be removed by spot polishing not objectionable.
- Surface imperfections, that can be removed by automatic buffing, not objectionable.
- No objectionable surface imperfections that would be highlighted by electro-chemical polishing. Where surface waviness (flatness) noted by light reflection is a reason for rejection, special agreement should be reached.
End Finish
- Surface finish of no importance
- Protective coatings:
Anodize (non decorative)
Chromate
Heavy paint
Matt or wrinkle finish - Decorative coatings:
Lacquers
Enamels
Plating (A1)
Chemical finish
Polished finish - Structural parts (high stress areas)
Plating (Zn).
Electrostatic plating
