GMW4700 |
This specification covers the basic requirements for barrel or
rack electrodeposited zinc alloy plating over a ferrous substrate.
Various alloy platings with supplementary treatments are covered by
this specification.
Zn- Ni plating is available in two types: Type A and Type B. Zn-
Ni Type B plating has higher corrosion resistance performance than
Zn- Ni Type A. Zn- Ni Type B must have supplementary sealers on top
of the conversion coating. The engineering drawing with GMW4700 Zn-
Ni without any type will default to Type A. In case of Type A
electrodeposits may be applied with or without supplementary
sealers meeting the performance requirements. Table 1 lists the
zinc alloy finishes covered by this specification.
This specification covers functional requirements only. Cosmetic
requirements such as brightness, shades, tint, etc. are not
defined. Material approved to this specification may not meet
special cosmetic/ appearance requirements, and will have to be
agreed upon by the purchaser and applicator.
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