Modification of a commercial ultrasonic bond tester for quantitative measurements in sheet-molding compound lap joints

Journal Article · Thu Apr 01 04:00:00 EST 1993 · Materials Evaluation; (United States)

OSTI ID:6601241

Papadakis, E P ^[1]; Chapmann, II, G B ^[2]

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1. Iowa State Univ., Ames (United States)
2. Chrysler Corp., Madison Heights, MI (United States)

A method has been devised to obtain quantitative nondestructive evaluation (NDE) measurements from a commercial ultrasonic adhesive bondtester designed for GO/NO-GO qualitative sorting. The method requires the connection of one electric meter across two points in the alarm circuit of the instrument. Further, the method requires the choice of proper referencing specimens as standards by a statistical method. The principle is that the reference specimens must be only marginally better than the barely acceptable adhesive bons. With the reference specimens and the new output, the instrument can be used to make measurements that correlate with adhesive bond strength even in the presence of bonds that fail partly by substrate delamination. With the reference specimens and the built-in alarm mode of the instrument, measurements can be made to define a probability of detection (POD) for disbonds vs. disbond size. With this POD in hand, one can define a specification for an adhesive lap joint in terms of an acceptable percentage of bonded area. This specification is in use. The bond test instrument is in use on adhesive bonds in sheet-molding compound (SMC) and continues to be cost-effective according to the Deming Inspection Criterion. Use of the bondtester has permitted one automotive manufacturer to continue and expand its utilization of adhesively bonded SMC body panels.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6601241
• Journal Information: Materials Evaluation; (United States), Journal Name: Materials Evaluation; (United States) Vol. 51:4; ISSN MAEVAD; ISSN 0025-5327
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420500* -- Engineering-- Materials Testing
ACOUSTIC TESTING
ADHESIVES
AUTOMOTIVE INDUSTRY
BONDING
DATA
EXPERIMENTAL DATA
FABRICATION
INDUSTRY
INFORMATION
JOINING
JOINTS
LAP WELDS
MATERIALS TESTING
MEASURING INSTRUMENTS
MODIFICATIONS
NONDESTRUCTIVE TESTING
NUMERICAL DATA
OPERATION
TESTING
ULTRASONIC TESTING
WELDED JOINTS