NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Ultrasonic wave velocity measurement in small polymeric and cortical bone specimensA system was refined for the determination of the bulk ultrasonic wave propagation velocity in small cortical bone specimens. Longitudinal and shear wave propagations were measured using ceramic, piezoelectric 20 and 5 MHz transducers, respectively. Results of the pulse transmission technique were refined via the measurement of the system delay time. The precision and accuracy of the system were quantified using small specimens of polyoxymethylene, polystyrene-butadiene, and high-density polyethylene. These polymeric materials had known acoustic properties, similarity of propagation velocities to cortical bone, and minimal sample inhomogeneity. Dependence of longitudinal and transverse specimen dimensions upon propagation times was quantified. To confirm the consistency of longitudinal wave propagation in small cortical bone specimens (< 1.0 mm), cut-down specimens were prepared from a normal rat femur. Finally, cortical samples were prepared from each of ten normal rat femora, and Young's moduli (Eii), shear moduli (Gij), and Poisson ratios (Vij) were measured. For all specimens (bone, polyoxymethylene, polystyrene-butadiene, and high-density polyethylene), strong linear correlations (R2 > 0.997) were maintained between propagation time and distance throughout the size ranges down to less than 0.4 mm. Results for polyoxymethylene, polystyrene-butadiene, and high-density polyethylene were accurate to within 5 percent of reported literature values. Measurement repeatability (precision) improved with an increase in the wave transmission distance (propagating dimension). No statistically significant effect due to the transverse dimension was detected.
Document ID
20040172922
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Kohles, S. S.
(University of Wisconsin Madison 53792, United States)
Bowers, J. R.
Vailas, A. C.
Vanderby, R. Jr
Date Acquired
August 22, 2013
Publication Date
August 1, 1997
Publication Information
Publication: Journal of biomechanical engineering
Volume: 119
Issue: 3
ISSN: 0148-0731
Subject Category
Life Sciences (General)
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
NASA Discipline Musculoskeletal

Available Downloads

There are no available downloads for this record.
No Preview Available