A reader asks, "Our company designs medical implants and tools. We do not actually manufacture anything, everything is outsourced. Corrosion issues arise every couple of months and we try to address them but we do not specialize in this area. We discuss these issues with our manufacturers, electro-polishing/passivating suppliers and we consult standards such as ASTM F-86 and ASTM A967. No matter what we do, we continue to see corrosion ruin expensive instruments.

The worst instruments are the ones that surgeons use to measure depths such as depth gauges and graduated drill guides (materials are 300 series, 400 series, 17-4 PH S/S, Carpenter 455, also forgings, usually from Europe made out of 420 S/S). Many times, due to the application of the instrument such as a drill guide, we are limiting to harder materials which are prone to corrosion. It is a “catch-22”. Anyways, it would be great to see some advice concerning this issue.