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Hydrogen Relief treatment on spring washers

September 21, 2011

For a spring washer, what is the effect of hydrogen relief treatment on salt spray life for zinc cobalt plating with trivalent passivation.
Is hydrogen Embrittlement relief necessary for zinc plated spring washer (IS:2507, grade 5)?
(No cracks were observed when the zinc plated spring washers were subjected to 4-5 times the nominal torque)

Jimit Kansara
Mechanical Engineer - Mumbai, India

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Dear Jimit Kansara,
Hydrogen relief treatment and salt spray are entirely different.
Salt spray is to check the corrosion behaviour.
Hydrogen relief treatment is to release the Hydrogen from the Base material before, passivation process.
Hydrogen relief treatment temperature & time will vary for the base material Tensile strength before Plating .
If, your base material strength is less than 1000 Mpa before plating , no need of Hydrogen relief treatment

Kannan Boopathi
- Salem, Tamilnadu, India
September 23, 2011

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Dear Jimit Kansara,

Hydrogen relief treatment in not related to salt spray.
Salt spray is to check the corrosion behaviour.

If your part's tensile strength is more than 1000 MPa before plating, you need to do the Hydrogen de-embrittlement process.
Temperature and time will vary depending on base material strength before plating.
Refer to ISO 9588 for more detail.

Kannan Boopathi
- Salem, TamilNadu, India
September 26, 2011