Surface
Coating
Thickness (um) Color
SST
(hours)
PCT
(hours)
Nickel Ni+Ni 10-20um Bright Silver
>24-72 >24-72
Ni+Cu+Ni
Black Nickel Ni+Cu+Ni 10-20um Bright Black >48-96 >48
Cr3+Zinc Zn 5-8um Bright Blue >16-48
C-Zn Shining Color >36-72
Sn Ni+Cu+Ni+Sn 10-25um Silver >36-72 >48
Au Ni+Cu+Ni+Au 10-15um Gold >12 >48
Ag Ni+Cu+Ni+Ag 10-15um Silver >12 >48
Epoxy Epoxy 10-20um Black, Grey >48
Ni+Cu+Epoxy 15-30um >72-108
Zn+Epoxy 15-25um >72-108
Passivation --- 1-3um Dark Grey Temporary Protection
Phosphated --- 1-3um Dark Grey Temporary Protection

Note:

1.
Different plating,different SST Result.Salt Spray Test Results, which is plated by grinding(small size magnets), is better than the one, which is coated by hanging up(big size magnets).

2. Salt Spray Test(SST) test condition: 5% NaCl, 35℃, continuously spray a certain time, check if there is corrosion on coating surface.

3. Pressure Cooking Test(PCT) test condition: 2 atm, 95% RH(relative humidity), 121℃, to test the coating adhesion. Notes:The products coating Zinc, passivated/phosphated, or coating Epoxy are not suitable for PCT.

4. Other methods to test the coating quality: drop test, cross cut test, heating and spilling test, constant temperature and humidity test,etc.