Hard Anodizing

           Sulfuric Hard anodize is formed by using an electrolytic solution of sulfuric acid at a lower temperature and it has higher wear resistance. This will produce a Rockwell C-scale rating of 60-70. This is an excellent coating for many wear situations. Hard anodize is formed by using an electrolytic solution of sulfuric acid at approximately 32° F and a current density of 23 to 37 Amps per square foot. The process will run for 20 to 120 minutes depending on the alloy used and desired coating thickness. This will produce a generally gray coating 10µm to 50µm thick.

Properties:

Hard  anodizing provides for several desirable qualities such as:

• Corrosion Resistance (336+ Hours salt spray resistance )
• High Durability (file hard, 60-70 on Rockwell C-scale)
• Electrical Insulation (800 V / mil thickness)

Hard anodize coatings may be dyed a variety of colors. However, due to its naturally darker appearance, dyeing does not produce the vibrant colors that a sulfuric anodize will. Additionally, the required sealing process after dyeing does slightly reduce hardness.

Materials:

Hard anodizing works very well with 6000, 5000, and 7000 series alloys. High-copper 2000 series alloys can present some difficulties and should be avoided if possible. As with all forms of anodizing high-silicon die castings are not recommended.

 If you want to start an anodizing unit  contact us