ASTM E1065-99

Standard Guide for Evaluating Characteristics of Ultrasonic Search Units

SCOPE
1.1 This guide describes measurement procedures for evaluating certain characteristics of ultrasonic search units (also known as "transducers") that are used with ultrasonic examination instrumentation. This guide describes means for obtaining performance data that may be used to define the acoustic and electric responses of ultrasonic search units.  
1.2 The procedures are designed to measure search units as individual components (separate from the ultrasonic test instrument) using commercial search unit characterization systems or using laboratory instruments such as signal generators, pulsers, amplifiers, oscilloscopes, and waveform analyzers.  
1.3 The procedures are applicable to manufacturing acceptance and incoming inspection of new search units or to periodic performance evaluation of search units throughout their service life.  
1.4 The procedures in Annexes A1 to A6 are generally applicable to ultrasonic search units operating within the 0.4 to 10 MHz range. Annex A7 is applicable to higher frequency immersion search unit evaluation. Annexes under development will be added to the guide when available and will apply to measurement of the sound field patterns from angle-beam and contact straight-beam search units, alternative means for making measurements of characteristics, and the like.  
1.5 The values stated in inch-pound units are to be regarded as standard.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Jun-1999
• ICS: 17.140.01 - Acoustic measurements and noise abatement in general
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.06 - Ultrasonic Method

Relations

• Replaced By: ASTM E1065-99(2003) - Standard Guide for Evaluating Characteristics of Ultrasonic Search Units
• Effective Date: 10-Jul-2003
• Referred By: ASTM E2491-23 - Standard Guide for Evaluating Performance Characteristics of Phased-Array Ultrasonic Testing Instruments and Systems
• Effective Date: 10-Jun-1999
• Referred By: ASTM E2775-16 - Standard Practice for Guided Wave Testing of Above Ground Steel Pipework Using Piezoelectric Effect Transduction
• Effective Date: 10-Jun-1999
• Referred By: ASTM E3166-20e1 - Standard Guide for Nondestructive Examination of Metal Additively Manufactured Aerospace Parts After Build
• Effective Date: 10-Jun-1999
• Referred By: ASTM E1774-17(2022) - Standard Guide for Electromagnetic Acoustic Transducers (EMATs)
• Effective Date: 10-Jun-1999
• Referred By: ASTM E2373/E2373M-19 - Standard Practice for Use of the Ultrasonic Time of Flight Diffraction (TOFD) Technique
• Effective Date: 10-Jun-1999
• Referred By: ASTM E213-22 - Standard Practice for Ultrasonic Testing of Metal Pipe and Tubing
• Effective Date: 10-Jun-1999
• Referred By: ASTM E127-20 - Standard Practice for Fabrication and Control of Flat Bottomed Hole Ultrasonic Standard Reference Blocks
• Effective Date: 10-Jun-1999
• Referred By: ASTM E2904-22 - Standard Practice for Characterization and Verification of Linear Phased Array Ultrasonic Probes
• Effective Date: 10-Jun-1999
• Referred By: ASTM E2375-22 - Standard Practice for Ultrasonic Testing of Wrought Products
• Effective Date: 10-Jun-1999

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: E 1065 – 99
Standard Guide for
Evaluating Characteristics of Ultrasonic Search Units
This standard is issued under the fixed designation E 1065; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope Standard Methods for Testing Single Element Pulse-Echo
Ultrasonic Transducers
1.1 This guide covers measurement procedures for evaluat-
ing certain characteristics of ultrasonic search units (also
3. Terminology
known as “transducers”) that are used with ultrasonic exami-
3.1 Definitions—For definitions of terms used in this guide,
nation instrumentation. This guide describes means for obtain-
see Terminology E 1316.
ing performance data that may be used to define the acoustic
3.2 Definitions of Terms Specific to This Standard:
and electric responses of ultrasonic search units.
3.2.1 aperture—the dimension(s) of the active area of the
1.2 The procedures are designed to measure search units as
piezoelectric element of the search unit as established by
individual components (separate from the ultrasonic test instru-
experimentation.
ment) using commercial search unit characterization systems
3.2.2 bandwidth (BW)— that portion of the frequency
or using laboratory instruments such as signal generators,
response that falls within given limits. In this text, the limits
pulsers, amplifiers, oscilloscopes, and waveform analyzers.
used are the -6 dB level, as measured from the peak of the
1.3 The procedures are applicable to manufacturing accep-
frequency response. The equation used for BW is:
tance and incoming inspection of new search units or to
periodic performance evaluation of search units throughout BW 5 ~f 2 f !/f 3 100 (1)
u 1 c
their service life.
where:
1.4 The procedures in Annex A1-Annex A6 are generally
f = upper frequency,
u
applicable to ultrasonic search units operating within the 0.4 to
f = lower frequency, and
10 MHz range. Annex A7 is applicable to higher frequency
f = center frequency.
c
immersion search unit evaluation. Annex A8 describes a guide
Bandwidth is expressed as a percentage.
for measuring sound beam profiles in metals from contact
3.2.3 center frequency (f )—the frequency value calculated
c
straight-beam search units. Additional Annexes, such as sound
to be at the center of the bandwidth limits.
beam profiling for angle-beam search units in metal and
3.2.4 depth of field (F )—as measured on the on-axis profile
D
alternate means for search unit characterization, will be added
of a focused search unit, that portion of the sound beam that
when developed.
falls within given limits.
1.5 The values stated in inch-pound units are to be regarded
3.2.5 focal length (F )—for focused search units, the dis-
L
as standard.
tance from the lens to the focal point.
1.6 This standard does not purport to address all of the
3.2.6 focal point (F )—for focused search units, the point
p
safety concerns, if any, associated with its use. It is the
along the acoustic axis of the beam in water at which the peak
responsibility of the user of this standard to establish appro-
(maximum) pulse-echo amplitude response is recorded from a
priate safety and health practices and determine the applica-
ball target reflector.
bility of regulatory limitations prior to use.
3.2.7 frequency response—the pulse-echo response of the
search unit measured as a function of frequency. (This term
2. Referenced Documents
also referred to as frequency spectrum.)
2.1 ASTM Standards:
3.2.8 nominal frequency (f )—the frequency stated on the
2 nom
E 1316 Terminology for Nondestructive Examinations
label supplied by the manufacturer.
2.2 Other Document:
3.2.9 on-axis profile—a sequence of measurements made
along the acoustic axis of the beam of the search unit.
3.2.10 peak frequency (f )—the frequency value at the
p
This guide is under the jurisdiction of ASTM Committee E-7 on Nondestructive
maximum amplitude of the frequency response.
Testing and is the direct responsibility of Subcommittee E07.06 on Ultrasonic
Method.
Current edition approved June 10, 1999. Published August 1999. Originally
e1 3
published as E 1065 – 85. Last previous edition E 1065 – 98 . Available from the American Institute of Ultrasonics in Medicine, 14750
Annual Book of ASTM Standards, Vol 03.03. Sweitzer Lane, Suite 100, Laurel, MD 20707-5906.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
E1065–99
3.2.11 pulse duration—the length of the sinusoidal burst electrical impedance may also be obtained using values re-
used to exite the search unit as expressed in time or number of corded from the sinusoidal burst techniques as outlined in
cycles (sometimes referred to as tone-burst). Annex A5.
3.2.12 pulse echo sensitivity—a measurement that compares 4.1.4.2 d-c Resistance—The d-c resistance of the search
the amplitude of the applied voltage with the amplitude of the unit may provide information regarding the electrical tuning
pulse-echo voltage recorded from a specified target. elements. Measurements are made across the terminals of the
unit.
3.2.13 shock excitation—a short electrical impulse that is
applied to the search unit. The impulse is typically a negative- 4.1.5 Sound Field Measurements—The objective of these
going voltage spike of fast rise time and short duration. measurements is to establish parameters such as the on-axis
and transverse sound beam profiles for immersion flat and
3.2.14 transverse profile—sequence of measurements made
focused search units.
along a line perpendicular to the acoustic axis of the beam of
the search unit. 4.1.5.1 Annexes A6 and A8 of this guide describe ways for
making sound field measurements for both immersion flat and
3.2.15 waveform duration—the time interval or duration
focused search units in water and contact straight-beam search
over which the unrectified signal or echo from a specified
units in metal. The literature discusses several ways for making
target exceeds a selected amplitude level as related to the
these measurements, but the techniques described are relatively
maximum amplitude of the signal or echo (for example, −20
simple and easily performed.
or −40 dB).
4.1.5.2 Means are recommended for making measurements
4. Summary of Guide in an immersion tank, thereby allowing either pulse-echo (ball
target) or hydrophone receiver techniques to be followed. The
4.1 The acoustic and electrical characteristics which can be
goal is to provide measurements to evaluate the characteristics
described from the data obtained by procedures outlined in this
of search units or to identify changes that may occur as a
guide are described as follows:
function of time or use, or both.
4.1.1 Frequency Response—The frequency response may
4.1.5.3 None of the measurements of sound beam patterns
be obtained from one of two procedures: (a) shock excitation
are intended to define limits of performance. They are designed
and (b) sinusoidal burst. Annex A1 describes procedures for
to provide a common means for making measurements that
obtaining frequency response for immersion and zero-degree
may be used to define the initial and inservice performance.
contact search units. Annex A2 describes the procedure for
obtaining bandwidth characteristics.
NOTE 2—No procedure is given for measuring sound beam profile
characteristics for angle-beam search units. Several potential approaches
4.1.2 Relative Pulse-Echo Sensitivity (S )—The relative
rel
are being considered, but have not yet gained subcommittee agreement
pulse-echo sensitivity may be obtained from the frequency
(1).
response data obtained using the sinusoidal burst procedure
NOTE 3—Frequency Response Displays. The frequency responses in
described in Annex A1. The value is obtained from the
Fig. 1 and Fig. 2 and throughout the text are displayed as a linear
relationship of the amplitude of the voltage applied to the
amplitude (not logarithmic) response as a function of frequency. The
search unit and the amplitude of the pulse-echo signal received
recording or line drawing shows only the positive component or envelope
from a specified target. Annex A3 describes the procedure for
of the responses. While this is the normal display for a spectrum analyzer,
obtaining pulse-echo sensitivity.
the sinusoidal burst response is shown as only one-half of the actual
sinusoidal wave.
NOTE 1—Values for applied and received power, from which insertion
loss might be determined are not covered with procedures described in this
5. Significance and Use
guide.
5.1 This guide is intended to provide standardized proce-
4.1.3 Time Response—The time response provides a means
dures for evaluating ultrasonic search units. It is not intended to
for describing the radio frequency (rf) response of the wave-
define performance and acceptance criteria, but rather to
form. A shock excitation, pulse-echo procedure is used to
provide data from which such criteria may be established.
obtain the response. The time or waveform responses are
5.2 These procedures are intended to evaluate the charac-
recorded from specific targets that are chosen for the type of
teristics of single-element piezoelectric search units.
search unit under evaluation (for example, immersion, contact
5.3 Implementation may require more detailed procedural
straight beam, or contact angle beam). Annex A4 describes the
instructions in a format of the using facility.
procedures for measuring time response.
5.4 The measurement data obtained may be employed by
4.1.4 Electrical Impedance:
users of this guide to specify, describe, or provide a perfor-
4.1.4.1 Complex Electrical Impedance—The complex elec-
mance criteria for procurement and quality assurance, or
trical impedance may be obtained with commercial impedance
service evaluation of the operating characteristics of ultrasonic
measuring instrumentation, and these measurements may be
search units. All or portions of the guide may be used as
used to provide the magnitude and phase of the impedance of
determined by the user.
the search unit over the operating frequency range of the unit.
These measurements are generally made under laboratory
conditions with minimum cable lengths or external accessories
and in accordance with the instructions of the instrument 4
The boldface numbers in parentheses refer to a list of references at the end of
manufacturer. The value of the magnitude of the complex this test method.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
E1065–99
FIG. 1 Test Data Available from Shock Excitation Procedure
FIG. 2 Test Data Available from Sinusoidal Burst Technique
5.5 The measurements are made primarily under pulse-echo capability, breakdown voltage, wear properties of contact units,
conditions. To determine the relative performance of a search
radio-frequency interference, and the like.
unit as either a transmitter or a receiver may require additional
5.7 Care must be taken to ensure that comparable measure-
tests.
ments are made and that users of the guide follow similar
5.6 While these procedures relate to many of the significant
procedures. The conditions specified or selected (if optional)
parameters, others that may be important in specific applica-
may affect the test results and lead to apparent differences.
tions may not be treated. These might include power handling
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
E1065–99
5.8 Interpretation of some test results, such as the shape of quency response, peak frequency, bandwidth, bandwidth center
the frequency response curve, may be subjective. Small irregu-
frequency, and time response may be obtained.
larities may be significant. Interpretation of the test results is
6.2 Fig. 2 illustrates the typical results obtained using the
beyond the scope of this guide.
sinusoidal burst technique. Values may be obtained for fre-
5.9 Certain results obtained using the procedures outlined
quency response, peak frequency, bandwidth, bandwidth center
may differ from measurements made with ultrasonic test
frequency, relative pulse-echo sensitivity, and magnitude of the
instruments. These differences may be attributed to differences
electrical impedance from the data recorded with this tech-
in the nature of the experiment or the electrical characteristics
nique.
of the instrumentation.
5.10 The pulse generator used to obtain the frequency
7. Keywords
response and time response of the search unit must have a rise
time, duration, and spectral content sufficient to excite the
7.1 aperture; bandwidth; characterization; contact testing;
search unit over its full bandwidth, otherwise time distortion
depth of field; focal point; frequency response; immersion
and erroneous results may result.
testing; peak frequency; search unit; sound beam profile; time
response; ultrasound
6. Typical Results Obtainable from Tests Described in
Annex A1-Annex A5
6.1 Fig. 1 illustrates some of the typical results that may be
obtained using shock excitation techniques. Values for fre-
ANNEXES
(Mandatory Information)
A1. MEASUREMENT OF FREQUENCY RESPONSE
A1.1 Introduction—The frequency response (also known oscilloscope, and spectrum analyzer. Fig. A1.3 describes typi-
as frequency spectrum) is a measure of the amplitude of the cal components used to measure the frequency response of a
pulse-echo response from a given target as a function of digitized rf waveform. The system consists of a search unit,
frequency. This response is used as the basis for establishing
pulser, receiver, gate that can be adjusted to capture the echo
other operating parameters of the search unit including peak
waveform, analog to digital converter (digitizer), Fourier
frequency, center frequency (see Annex A1), bandwidth (see
transform calculator, and display. To make the measurement,
Annex A2) and sensitivity (see Annex A3). Sketches of typical
an excitation pulse is applied to the search unit and an echo is
response curves are shown in Fig. A1.1. These sketches are
obtained from a specific target. The gated echo is monitored on
used to describe two co
...