Hydrogen Embrittlement

[Bill]

In previous posts we have talked about plating your bolts to lessen the electrolysis, which can cause bimetal corrosion.
Like bare steel, copper, brass coming in contact with aluminum.
Well this is the rest of the story…
Have you ever had a bolt or nut even washers or other fasteners just shatter when you tighten down on them?
And you just had them plated to look their best only to see them in pieces all over the floor?
In talking to a metallurgist the other day about the profits of plating bolts to keep the electrolysis down on your just restored engine and other parts of your Honda 600’s Aluminum Engine, he spoke of Hydrogen Embrittlement .
The process by which various metals, most importantly high-strength
steel , become
brittle
and
fracture
following exposure to
hydrogen .
Hydrogen embrittlement is often the result of unintentional introduction of hydrogen into susceptible metals during forming or finishing operations and increases cracking in the material.
(Like when your plating bolts or other fasteners.)
Often when you have a plating shop plate your bolts with gold cad or gold zinc, hydrogen can be introduced and cause Hydrogen embrittlement.
The easy fix is to talk to the plating shop and let them know that these fasteners are going to be used on your car.
Mention Hydrogen Embrittlement and if they don’t know what your talking about, then it might be a time to find another plating shop.

[pommecoing]

Hello,
I have had problems in the recent past when I had some brake parts replated. Everything was ok whith most of the items. But when I put back the yokes on the calipers, I heard a series of "pops" and "fizz" until these springs broke in several parts.
Talking with the person who did the job, he said I should have told him before that these parts were springs. He would have done an other treatment to avoid the hydrogen embrittlement.
Thank you