Silver colored contamination after handling stainless steel parts 1

[EngineerDave]

After giving the white glove treatment to several small machined stainless steel parts, dark silver colored contamination was present on my hands?

Any idea of what could be causing this? I have one idea that it could be free iron. Does anyone have any experience with this?

 

[kenvlach]

This is some sort of machining debris. It would be a good idea to examine under high magnification; a lot of SS alloys do not machine smoothly, but sharper tooling may help.

I suggest deburring, preferably by chemical polishing, electrocleaning or electropolishing. This will remove any slivers and embedded debris.

 

[mcguire]

Kevlach is correct. The fact that the debris is silver confirms that it is the stainless. Free iron would turn black or red from oxidation; stainless stays silver colored.