Re: Source for stainless steel powder
If the intent is only to fill the epoxy for better modulus or less thermal expansion I can not see a reason to specifically use stainless steel powder. Since the epoxy is in any case several magnitudes softer than the filler powder you could use just as well aluminum powder or even washed quartz sand. That said, if you want to drill or tap the hardened epoxy, the sand would not be good for your tools but the aluminum better than the steel.
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