Engine Titanium Consortium - Center for Nondestructive Evaluation ...

focusing with respect to the scale of the microstructure on the form of the signal and noise
distributions, and the rules required to determine the distribution of signal-in-the-presence-of-noise
from the noise distribution and the flaw free noise response. All of these will be considered as
influenced by the presence of anisotropy and beam modification by the part geometry. Results of
these software and procedural advances will be integrated and provided to the OEMs for their
internal use. These uses are anticipated to include life management calculations, such as
consideration of the likely effects on POD of proposed changes in inspection systems and
procedures such as scan plans, transducer properties, gate widths, etc.
POD for Titanium Forgings: Efforts to acquire naturally occurring hard alpha inclusion data will be
continuously made. Possible sources include field and manufacturing finds, the utility of which will
depend on the degree to which appropriate procedures are utilized to fully characterize the 3-D
shapes of these finds. Information gained during the forging studies of the TRMD program will also
be used. This information will be used, as appropriate, to provide POD estimates. The
methodology will be used to evaluate the improvements in POD afforded by developments of the
Production Inspection Task 1.3.2.
Objective/Approach Amendments: Objective and approach remain as originally proposed in July
1998.
Progress (January 1, 2002 – March 31, 2002):
On March 16, 2000 the FAA issued instructions to end all expenditures on Task 3, other than those
associated with the RDB technical plan, with a restart to be considered once the sources of the
discrepancy had been resolved. Hence the vast majority of the work on this task was terminated.
A low level of effort has continued with the objective of coordinating with the Production tasks the
work that is needed to support the POD effort. This had the objectives of ensuring that the
fundamental studies measurements would produce the information needed by the POD group and
that forging samples being produced would support the POD methodology. To these ends, the
progress of the fundamental studies and forgings tasks have been monitored in terms of findings
such as the degree of anisotropy and inhomogeneity of noise that has been observed in billet and
forging materials and plans to prepare samples that will provide information to be used in POD
assessment. In the latter context, particular attention has been paid to the fabrication of a forging
containing synthetic hard-alpha inclusions and flat bottom holes. On March 14, 2001, the FAA
indicated that work is to be resumed on sub-tasks 3.1.1 and 3.1.2, and planning for that restart
initiated.
Plans (April 1, 2002 – June 30, 2002):
Planning of the restart of subtask 3.1.2 will take place after the completion of the planning for
restart of subtask 3.1.1. In the meantime, continued interactions with the Fundamental Studies and
Production Tasks will occur, with the initial effort focused on the design of the forging POD sample.
Quarterly Report – January 1, 2002 –March 31, 2002
print date/time: 6/6/2002 - 8:39 AM – Page 101