Frequently Asked Questions and Answers for Blue Etch Anodize (BEA):
Q1 – Can any material be BEA processed?
A1 – No, BEA can only be used to process titanium alloys.
Q2 – Can BEA be done on a portion of a part (i.e., a localized inspection)?
A2 – In general, the answer is no. However, if only a portion of a part on its end needs to be BEA, it is possible to hang and immerse only that portion of the part. Note however that the exact location of the processed level is not accurately controlled due to tank agitation.
Q3 – How many times can a part to BEA processed?
A3 – The quantity of times a part can be BEA processed varies by aerospace Primes. In general, most allow 2 BEA’s before requiring a special approval to do more.
Q4 – How much material is removed by BEA?
A4 – Typical BEA involves the removal of .00008″ (.002 mm) of base material before its anodize step. The anodize thickness is essentially the same, hence a net change of zero. This applies if the part is returned in its blue color condition. If the part is instead requested to be backstripped before return to customer, the approximate overall loss of material is again .00008″ (.002 mm).