MIL-HDBK-1110
identify and quantity the metals present in a coating. Their
methods of operation are beyond the scope of this document.
11.3.7
Forming Conclusions and Preparing Reports. Field and
laboratory data should be analyzed logically and systematically
to form conclusions as to the causes of paint failure. No data
should be overlooked, and the conclusions should be consistent
with the data. The report should include conclusions and
recommendations requested by the activity for which the analysis
was made.
The report is perhaps the most important part of the
failure analysis, because it presents the findings and
conclusions of the investigation. No amount of good field or
laboratory work will be useful unless it is presented well in the
report. There must be a clear, systematic, and logical
presentation of the findings, so that the conclusions are well
supported. The report should not contain errors or otherwise be
subject to challenge. Where conclusions are not firm, the extent
of uncertainty should be stated.
11.4
Expert System for Failure Analysis. An expert system
for failure analysis provides a systematic approach first to make
a preliminary identification based on visual observations and
then to verify it with supplementary information. The initial
identification is based upon the answers to a series of questions
designed to distinguish one type of failure from another.
Decision trees 1 and 2 are used for this, one for surface defects
and one for film failures. This same approach can be used in an
expert system for a computer. The importance of a systematic
approach cannot be overemphasized. One should be careful not to
make permanent decisions on types and causes of failure until all
the evidence is considered.
The first step in the identification of a coating
failure is to determine which decision tree to use. Tree l for
cosmetic defects should be used if only surface damage is
present, i.e., if the surface coat has not been completely
penetrated to the underlying coat or structural substrate. Tree
2 for film failures should be used if coating damage has
completely extended through the surface coat.
After a preliminary decision of the type of failure has
been made, look at the additional comments in the verification
section below to obtain further support for this selection. If
this information does not support the initial decision, reexamine
the evidence or reconsider answers to the decision tree, until
you are satisfied that you received the best overall answer.
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