Cad plated bolting - temp limits
Cad plated bolting - temp limits
(OP)
I would like to know why many specs call for not using cad plated bolting in applications above 200 degrees C. Is it an HSE issue or a coating integrity issue? I am referring to A320 L7 bolts.





RE: Cad plated bolting - temp limits
RE: Cad plated bolting - temp limits
RE: Cad plated bolting - temp limits
It appears that SME has only been observed for those metal combinations in which LME can occur. Prerequisite for SME failure are a) the presence of tensile stress (either residual or applied) and b) a crack initiation site (even a grain boundary) at the embrittler/substrate interface.
For Cd on high strength steel, most examples of delayed failure due to SME were for temperatures of 188oC or above. One sturdy for Cd/4340M reported failure at 38oC, M. Hasegawa and S. Nomura, JISI, Japan, vol. 7, p. 187 (1977).