Surface treatment process for Metal parts:

Surface treatment of Metal parts is a key process to improve product corrosion resistance,wear resistance,and aesthetics.By forming a protective layer or modified layer on the metal surface,it can adapt to different usage needs in different scenarios.Based on mainstream industrial processes,a precise 500 word introduction will be provided from the core characteristics and applicable scenarios

The mainstream processes can be divided into six categories:galvanizing process is the core anti-corrosion solution,including hot-dip galvanizing(zinc layer thickness of 80-150μm,salt spray test≥720 hours,suitable for carbon steel accessories in outdoor and marine environments),electroplating galvanizing(film thickness of 5-20μm,high precision,suitable for precision fasteners);Aluminum alloy exclusive anodizing process,ordinary type(film thickness 5-20μm,with anti-corrosion and decorative properties),hard type(film thickness 20-100μm,excellent wear resistance,suitable for moving parts);The spraying process includes powder spraying(with a film thickness of 60-120μm,strong weather resistance,and rich colors)and electrophoretic coating(with good adhesion and suitable for complex shaped accessories),meeting the dual requirements of corrosion prevention and aesthetics.

The chrome/nickel plating process focuses on wear resistance and decorative properties,with a hard chrome coating hardness of HV800-1000,suitable for mechanical moving parts;The thickness of the electroless nickel plating film is uniform and the corrosion resistance is outstanding.Passivation/phosphating is often used as a pre-treatment process.Stainless steel passivation can improve corrosion resistance,while steel phosphating can enhance the adhesion of subsequent coatings.In addition,the Dacromet process(salt spray test≥1000 hours,no hydrogen embrittlement)is suitable for high-strength fasteners,and the vacuum plating process can achieve high-end metallic colors,making it suitable for electronic decorative accessories.

The process selection should closely focus on the material(aluminum alloy with priority anodizing,carbon steel with galvanizing/spraying),environment(outdoor strong corrosion with hot-dip galvanizing/Dacromet),performance requirements(high wear resistance with hard chromium/hard anodizing),and compliance requirements(export to the EU must comply with RoHS and avoid hexavalent chromium).The core of quality inspection focuses on the duration of salt spray testing,coating adhesion(100 grid test≥0 level),and film thickness uniformity to ensure product stability and service life.