Five different types of chromium-free treatments

With the superior corrosion resistance of ZAM® maintained,
five different types of chromium-free treatments are available to suit various applications.
All of these treatments conform to the environmental regulations, including RoHS and ELV.

Anticorrosion mechanism of films

Mechanism of corrosion control
by chromate film

（1）Corrosion control with environmental deprivation

The chromate film covers the coating layer uniformly to
prevent direct contact with corrosion factors.

（2）Corrosion control with self-repairing function

If the chromate film is damaged due to processing for
instance, hexavalent chromium dissolves in a moist
environment to form an oxide film for self-repairing.

Mechanism of corrosion control by chromate film

Mechanism of corrosion control
by chromium-free film

（1）Corrosion control with environmental deprivation

The chromium-free film covers the coating layer uniformly
to prevent direct contact with corrosion factors.

（2）Corrosion control by self-repairing function

If the chromium-free film is damaged due to processing
for instance, soluble salt dissolves under a moist environment to
form insoluble salt at the damaged are forself-repairing.

Mechanism of corrosion control by chromium-free film