Electropolishing Case Study: Complex Assembly of Multiple Alloys Needing Improved Sealing Surface

Industry

Aerospace

MFG/METHOD

Assembly/Machined

ALLOY

304L stainless steel, molybdenum and glass

PROBLEM

The hermetic assembly is made of 304L stainless steel body and a molybdenum pin. They are glass fused in an oven. The glass baking operation created a green oxide layer, which needed to be removed. The hermetic assembly is subjected to a variety of tests to detect leaking and sealing breakdown. The hermetic assembly is part of a critical aerospace battery component.

SOLUTION

Electropolishing the hermetic assembly provided an oxide free, Brite Ultraclean surface. Able Electropolishing has a long history of success removing the discoloration from the glass to metal seal. The electropolished hermetic assemblies were subjected to stringent leakage mass spectrometer testing. Able Electropolishing passed all testing.

Note to engineer:Critical assemblies especially of dissimilar metals requires close examination. We can provide guidance on assuring the integrity of fitted components if you could provide a sample part or blueprint.