Is it safe to Chrome coat 4340?
Is it safe to Chrome coat 4340?
(OP)
Our shop reworked 4340 tube stock (AMS 6414) and created an area of undersize outer diameter.
It was proposed to chrome coat the affected surface and machine again to proper finish OD.
Would there be any deleterious effect? Hydrogen embrittlement, etc?
Is there a better process to build up or fill in the surface?
The stock is subsequently cad plated, heat treated to Rc 32-36, shot peened, epoxy primed, and painted black.
The final part is a critical aircraft part.
It was proposed to chrome coat the affected surface and machine again to proper finish OD.
Would there be any deleterious effect? Hydrogen embrittlement, etc?
Is there a better process to build up or fill in the surface?
The stock is subsequently cad plated, heat treated to Rc 32-36, shot peened, epoxy primed, and painted black.
The final part is a critical aircraft part.





RE: Is it safe to Chrome coat 4340?
Aside from this being a critical part there are too many subsequent operations on the affected part that chrome plating would interfere with or prevent.
RE: Is it safe to Chrome coat 4340?
RE: Is it safe to Chrome coat 4340?
Recently, I have had 4340H shafts chrome plated, also on undersize diameters, but after induction hardening and furnace tempering. An additional temper cycle was performed after the plating.
I also recommend getting customer approval on an engineering deviation since it appears you are dealing with a safety related component.
RE: Is it safe to Chrome coat 4340?
IMO, the statement says it all, I would not recommend it.
RE: Is it safe to Chrome coat 4340?
Chocolates,men,coffee: are somethings liked better rich!!
(noticed in a coffee shop)
RE: Is it safe to Chrome coat 4340?
RE: Is it safe to Chrome coat 4340?
RE: Is it safe to Chrome coat 4340?