Use of Magnetostrictive Sensor Monitoring Technology (MsSMT) … · 2007. 2. 6. · Use of...
Transcript of Use of Magnetostrictive Sensor Monitoring Technology (MsSMT) … · 2007. 2. 6. · Use of...
Use of Magnetostrictive Sensor Use of Magnetostrictive Sensor Monitoring Technology (Monitoring Technology (MsSMTMsSMT) for the ) for the Evaluation of Adhesively Bonded PatchEvaluation of Adhesively Bonded Patch
(Patent Pending)(Patent Pending)
Glenn Light, Ph.D.Glenn Light, Ph.D.Hegeon Kwun, Ph.D.Hegeon Kwun, Ph.D.
Sang Kim, Ph.D.Sang Kim, Ph.D.Robert SpinksRobert Spinks
Southwest Research InstituteSouthwest Research InstituteSan Antonio, TXSan Antonio, TX
Discussion of ProblemDiscussion of Problem
Defects in aircraft structure can sometimes be repaired using adhesively bonded patch
Once the bonded patch repair has been completed, it is necessary to inspect the region to– Verify that the defect is not growing
– Verify the quality of the patch
Technical ApproachTechnical Approach
Bond MsSM probe unit onto the aircraft structureCollect reference waveform (has data from the bonded region as well as the defect)Process collected data to determine changes in – Bond quality– Defect size
Laboratory Experiments of MsSM with Bonded Patch and Defect in Aluminum Plate
0.125-inch-thick,3 x 1 ft Aluminum Plate
1/16-inch-thick,8 x 4 inch Aluminum Patch
51-percent-thickness-deep,2-inch-long Notch Defect
MsS Probe
Aluminum with Patch Bonded over 51-Percent-Thickness-Deep, 2-Inch-Long Notch Defect
Initialpulse
Front Patch
Back Patch
Plate End
Notch
Aluminum with Patch Bonded and Defect Growing
Initialpulse
Before Placing a Notch
After Placing a 51%-thickness-deep Notch
1-inch-long
0.5-inch-long
1.5-inch-long
2-inch-long
After Applying Waveform Differential Algorithmin Time Domain to Monitor Notch Growth
Initialpulse
Before Placing a Notch
After Placing a 51%-thickness-deep Notch
Front PatchBack Patch
Plate End
1-inch-long
0.5-inch-long
1.5-inch-long
2-inch-long
Aluminum with Patch and Defect with Changes in the Bond Quality
Initialpulse
Patch with good bond
Patch with Partial Front Debond
Notch
Patch with Partial Front + Partial Back Debond
Patch with Total Front + Partial Back Debond
Complete Patch Debond
After Applying Waveform Differential Algorithmin Time Domain to Monitor Patch Bond
Initialpulse
Plate End
Notch
Patch with good bond
Patch with Partial Front Debond
Patch with Partial Front + Partial Back Debond
Patch with Total Front + Partial Back Debond
Complete Patch Debond
Relative Velocity Change of Guided Wave in Patch Region with Changes in the Bond Quality
Bon
ded
Patc
h
Deb
onde
d Pa
tchChanges in the Bond Quality
GoodBond
PartialFront debond
Partial Front+
PartialBack
Debond
TotalFront +
PartialBack
Debond
CompletePatch
Debond
ResultsResultsSouthwest Research Institute applied the MsSM to monitor the quality of adhesively bonded patch and the notch growing under the patch.
(1) Waveform differential algorithm was developed that allows the detection of a notch growing and bond-quality change in sequential MsS signals.
(2) Change of the bond quality in patch region could be identifiable using relative velocity change of guided wave.
Future Work to be Conducted on Future Work to be Conducted on MsSM MsSM with Bonded Nickel MsS Probewith Bonded Nickel MsS Probe
Laboratory evaluation on honeycomb composite structuresLaboratory evaluation on graphite epoxy patchesPreliminary development of flat sensor coil that could be read out by a remote sensorField demonstration of MsSM with bonded nickel MsS probe on aircraft structureInvestigation of variations in magnetic property of nickel MsS probe as a result of the aerospace environment