ASTM E837-99

Standard Test Method for Determining Residual Stresses by the Hole-Drilling Strain-Gage Method

SCOPE
1.1 This test method covers the procedure for determining residual stresses near the surface of isotropic linearly-elastic materials. Although the concept is quite general, the test method described here is applicable in those cases where the stresses do not vary significantly with depth and do not exceed one half of the yield strength. The test method is often described as "semi-destructive" because the damage that it causes is very localized and in many cases does not significantly affect the usefulness of the specimen. In contrast, most other mechanical methods for measuring residual stress substantially destroy the specimen. Since the test method described here does cause some damage, it should be applied only in those cases either where the specimen is expendable or where the introduction of a small shallow hole will not significantly affect the usefulness of the specimen.
1.2 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-Oct-2001
• ICS: 77.040.10 - Mechanical testing of metals
• Technical Committee: E28 - Mechanical Testing
• Drafting Committee: E28.13 - Residual Stress Measurement

Relations

• Replaced By: ASTM E837-01 - Standard Test Method for Determining Residual Stresses by the Hole-Drilling Strain-Gage Method
• Effective Date: 10-Oct-2001
• Referred By: ASTM G58-85(2015) - Standard Practice for Preparation of Stress-Corrosion Test Specimens for Weldments
• Effective Date: 10-Oct-2001
• Referred By: ASTM F3122-14(2022) - Standard Guide for Evaluating Mechanical Properties of Metal Materials Made via Additive Manufacturing Processes
• Effective Date: 10-Oct-2001
• Referred By: ASTM E1561-20 - Standard Practice for Analysis of Strain Gage Rosette Data
• Effective Date: 10-Oct-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: E 837 – 99 An American National Standard
Standard Test Method for
Determining Residual Stresses by the Hole-Drilling Strain-
Gage Method
This standard is issued under the fixed designation E 837; 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.
INTRODUCTION
The hole-drilling strain-gage method measures residual stresses near the surface of a material. The
method involves attaching strain gages to the surface, drilling a hole in the vicinity of the gages, and
measuring the relieved strains. The measured strains are then related to relieved principal stresses
through a series of equations.
1. Scope 3. Summary of Test Method
1.1 This test method covers the procedure for determining 3.1 A strain gage rosette with three or more elements of the
residual stresses near the surface of isotropic linearly-elastic general type schematically illustrated in Fig. 1 is placed in the
materials. Although the concept is quite general, the test area under consideration. The numbering scheme for the strain
method described here is applicable in those cases where the gages follows a clockwise (CW) convention (1).
stresses do not vary significantly with depth and do not exceed
NOTE 1—The gage numbering convention used for the rosette illus-
one half of the yield strength. The test method is often
trated in Fig. 1 differs from the counter-clockwise (CCW) convention used
described as “semi-destructive” because the damage that it
for some designs of general-purpose strain gage rosettes and for some
causes is very localized and in many cases does not signifi- other types of residual stress rosette. If a strain gage rosette with CCW
gage numbering is used, the residual stress calculation methods described
cantly affect the usefulness of the specimen. In contrast, most
in this test method still apply. The only change is a reversal in the
other mechanical methods for measuring residual stress sub-
assignment of the direction of the most tensile principal stress. This
stantially destroy the specimen. Since the test method de-
change is described in Note 7. All other aspects of the residual stress
scribed here does cause some damage, it should be applied
calculation are unaffected.
only in those cases either where the specimen is expendable or
3.2 A hole is drilled at the geometric center of the strain
where the introduction of a small shallow hole will not
gage rosette to a depth of about 0.4 of the mean diameter of the
significantly affect the usefulness of the specimen.
strain gage circle, D.
1.2 This standard does not purport to address all of the
3.2.1 The residual stresses in the area surrounding the
safety concerns, if any, associated with its use. It is the
drilled hole relax. The relieved strains are measured with a
responsibility of the user of this standard to establish appro-
suitable strain-recording instrument. Within the close vicinity
priate safety and health practices and determine the applica-
of the hole, the relief is nearly complete when the depth of the
bility of regulatory limitations prior to use.
drilled hole approaches 0.4 of the mean diameter of the strain
2. Referenced Documents gage circle, D.
3.3 Fig. 2 shows a schematic representation of the residual
2.1 ASTM Standards:
stress and a typical surface strain relieved when a hole is drilled
E 251 Test Methods for Performance Characteristics of
into a material specimen. The surface strain relief is related to
Metallic Bonded Resistance Strain Gages
the relieved principal stresses by the following relationship:
¯ ¯ ¯ ¯
This test method is under the jurisdiction of ASTM Committee E-28 on
e 5 ~A 1 B cos 2b!s 1 ~A 2 B cos 2b!s (1)
r max min
Mechanical Testing and is the direct responsibility of Subcommittee E28.13 on
Residual Stress Measurement.
Current edition approved Oct. 10, 1999. Published April 2000. Originally
published as E 837 – 81. Last previous edition E 837 – 95. The boldface numbers in parentheses refer to the list of references at the end of
Annual Book of ASTM Standards, Vol 03.01. this test method.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
E 837
(a) (b)
FIG. 1 Schematic Diagram Showing the Geometry of a Typical Three-Element Clockwise (CW) Strain Gage Rosette for the Hole-Drilling
Method
s 5 minimum (most compressive) principal stresses
min
present at the hole location before drilling,
b5 angle measured clockwise from the direction of
gage 1 to the direction of s ,
max
D 5 diameter of the gage circle,
D 5 diameter of the drilled hole.
3.3.1 The following equations may be used to evaluate the
¯ ¯
constants A and B for a material with given elastic properties:
¯
A 5 – a¯ ~11v! / ~2E! (2)
¯ ¯
B 5 – b / ~2E! (3)
where:
E 5 Young’s modulus,
v 5 Poisson’s ratio, and
FIG. 2 Definitions of Symbols
a¯ and b¯ are dimensionless, almost material-independent
constants (see Note 2). Slightly different values of these
where:
constants apply for a through-thickness hole made in a thin
e 5 relieved strain measured by a radially aligned
r
specimen and for a blind hole made in a thick specimen. The
strain gage centered at P,
¯ ¯
numerical values of these constants are provided in this test
A,B 5 calibration constants,
s 5 maximum (most tensile) and
method.
max
E 837
NOTE 2—The dimensionless coefficients a¯ and b¯ vary with hole depth,
3.3.4 It is assumed that the variations of the original stresses
as indicated in Table 1. They are both nearly material-independent. They
within the boundaries of the hole are small and that the
do not depend on Young’s modulus, E, and they vary by less than 1 % for
variation with depth is negligible. It is not necessary for the
Poisson’s ratios in the range 0.28 to 0.33. For a through-hole in a thin
original stresses outside of the hole location to be uniform.
plate, a¯ is independent of Poisson’s ratio.
4. Significance and Use
3.3.2 The relieved strains e , e , and e are measured by
1 2 3
4.1 Residual stresses are present in almost all structures.
three correspondingly numbered strain gages as shown in Fig.
They may be present as a result of manufacturing processes or
1. For specialized applications, a rosette with three pairs of
they may occur during the life of the structure. In many cases
strain gages arranged in directions1-2-3may be used (see
residual stresses are a major factor in the failure of a structure,
5.2.3). Measurement of these three relieved strains provides
particularly one subjected to alternating service loads or
sufficient information to calculate the principal stresses s
max
corrosive environments. Residual stress may also be beneficial
and s and their orientation b.
min
as, for example, compressive stresses produced by shot peen-
3.3.3 For reasons of pictorial clarity in Fig. 2, the principal
ing. The hole-drilling strain-gage technique is a practical
residual stresses s and s are shown as uniformly acting
max min
method for determining residual stresses.
over the entire region around the hole location. In actuality, it
is not necessary for the residual stresses to be uniform over
5. Strain Gages
such a large region. The relieved surface strains depend only on
5.1 A rosette comprising three single or pairs of strain gage
the principal stresses that originally existed at the boundaries of
grids shall be used.
the hole (2). The stresses beyond the hole boundaries do not
affect the relieved strains. Because of this, the hole-drilling NOTE 3—It is recommended that the gages be calibrated in accordance
with Test Methods E 251.
method provides a very localized measurement of residual
stresses. 5.1.1 The gages shall be arranged in a circular pattern,
TABLE 1 Numerical Values of Coefficients a¯ and b¯
Rosette A a¯b¯
Blind hole Hole Diameter, D /D Hole Diameter, D /D
0 0
Depth/D 0.30 0.35 0.40 0.45 0.50 0.30 0.35 0.40 0.45 0.50
0.00 .000 .000 .000 .000 .000 .000 .000 .000 .000 .000
0.05 .027 .037 .049 .063 .080 .051 .069 .090 .113 .140
0.10 .059 .081 .108 .138 .176 .118 .159 .206 .255 .317
0.15 .085 .115 .151 .192 .238 .180 .239 .305 .375 .453
0.20 .101 .137 .177 .223 .273 .227 .299 .377 .459 .545
0.25 .110 .147 .190 .238 .288 .259 .339 .425 .513 .603
0.30 .113 .151 .195 .243 .293 .279 .364 .454 .546 .638
0.35 .113 .151 .195 .242 .292 .292 .379 .472 .566 .657
0.40 .111 .149 .192 .239 .289 .297 .387 .482 .576 .668
Through Hole .090 .122 .160 .203 .249 .288 .377 .470 .562 .651
Rosette B a¯b¯
Blind Hole Hole Diameter, D /D Hole Diameter, D /D
0 0
Depth/D 0.30 0.35 0.40 0.45 0.50 0.30 0.35 0.40 0.45 0.50
0.00 .000 .000 .000 .000 .000 .000 .000 .000 .000 .000
0.05 .029 .039 .053 .068 .086 .058 .078 .102 .127 .157
0.10 .063 .087 .116 .148 .189 .134 .179 .231 .286 .355
0.15 .090 .123 .162 .205 .254 .203 .269 .343 .419 .504
0.20 .107 .145 .189 .236 .289 .256 .336 .423 .511 .605
0.25 .116 .156 .202 .251 .305 .292 .381 .476 .571 .668
0.30 .120 .160 .206 .256 .309 .315 .410 .509 .609 .707
0.35 .120 .160 .206 .256 .308 .330 .427 .529 .631 .730
0.40 .118 .158 .203 .253 .305 .337 .437 .541 .644 .743
Through Hole .096 .131 .171 .216 .265 .329 .428 .531 .630 .725
Rosette C a¯b¯
Blind Hole Hole Diameter, D /D Hole Diameter, D /D
0 0
Depth/D 0.40 0.45 0.50 0.55 0.60 0.40 0.45 0.50 0.55 0.60
0.00 .000 .000 .000 .000 .000 .000 .000 .000 .000 .000
0.05 .065 .084 .106 .130 .157 .105 .132 .158 .185 .217
0.10 .147 .191 .238 .293 .361 .250 .314 .373 .440 .519
0.15 .218 .281 .347 .420 .506 .391 .484 .570 .658 .754
0.20 .270 .343 .421 .504 .595 .506 .617 .719 .816 .912
0.25 .302 .381 .465 .554 .648 .591 .712 .823 .923 1.015
0.30 .321 .403 .491 .583 .679 .650 .778 .893 .994 1.081
0.35 .331 .415 .505 .599 .698 .690 .822 .939 1.041 1.125
0.40 .336 .421 .512 .608 .709 .719 .851 .970 1.073 1.154
Through Hole .316 .399 .494 .597 .707 .623 .723 .799 .847 .859
E 837
equidistant from the center of the rosette.
5.1.2 The principal gage axes shall be oriented in each of
three directions, (1) a reference direction, (2) 45° or 135° to the
reference direction, and (3) perpendicular to the reference
direction. Direction (2) bisects directions (1) and (3), (see Fig.
1).
5.2 Several different standardized rosettes are available to
meet a wide range of residual stress measurement needs. Fig.
3 shows three different rosette types.
5.2.1 Fig. 3 (a) shows the type A rosette, first introduced by
Rendleer and Vigness (3). This pattern is available in several
different sizes, and is recommended for general-purpose use.
5.2.2 Fig. 3 (b) shows thr type B rosette. This pattern has all
strain gage grids located on one side. It is useful where
measurements need to be made near an obstacle.
5.2.3 Fig. 3 (c) shows the type C rosette. This special-
purpose pattern has three pairs of opposite strain gage grids
that are to be connected as three half-bridges. It is useful where
large strain sensitivity and high thermal stability are required
(19).
NOTE 4—Standardized hole-drilling rosette patterns were first proposed
by Rendler and Vigness (3). The use of standardized rosette designs
greatly simplifies the calculation of the residual stresses.
5.3 The center of the gage circle shall be clearly identifiable
both before and after the drilling operation.
5.4 The application of the strain gage (cementing, wiring,
protective coating) shall closely follow the manufacturer’s
recommendations, and shall ensure the protection of the strain
gage grid during the drilling operation.
5.5 The strain gages shall remain permanently connected
and the stability of the installation shall be verified. A resis-
tance to ground of at least 20 000 MV is preferable.
6. Instrumentation
6.1 The instrumentation for recording of strains shall have a
−6
strain resolution of 62 3 10 , and stability and repeatability
−6
of the measurement shall be at least6 2 3 10 . The lead wires
from each gage should be as short as practicable and a
three-wire temperature-compensating circuit (4) should be
used with rosette types A and B. Half-bridge circuits should be
used with rosette type C, the resulting outputs of which are
designated e , e , and e .
1 2 3
NOTE 5—In general, surface preparation should be restricted to those
methods which have been demonstrated to induce no significant residual
surface stresses.
7. Specimen Preparation
7.1 The surface preparation prior to cementing the strain
gage shall conform to the recommendations of the manufac-
turer of the cement used to attach the strain gage.
7.1.1 A thorough cleaning and degreasing is required.
7.1.2 A smooth surface is usually necessary for strain gage
application. However, abrading or grinding that could appre-
ciably alter the surface stresses must be avoided.
4 FIG. 3 Hole-Drilling Rosettes
Strain gage patterns of these designs are manufactured by Measurements
Group, Wendell, NC.
E 837
8. Procedure (2) Drilling at very high speed (up to 400 000 rpm) with an
air turbine has also been used successfully in this application
8.1 Drilling:
(8). This technique is believed to be generally suitable except
8.1.1 To protect the strain gage grids, a margin of at least
for extremely hard materials such as stellite (7).
0.012 in. (0.30 mm) should be allowed between the hole
(3) End mills, carbide drills, and modified end mills have
boundary and the end loops of the strain gage grids. The need
been used successfully in a number of studies (3, 9, 10, 11).It
for this margin limits the maximum allowable diameter, D of
appears, however, that low-speed drilling with an end mill may
the drilled hole. The minimum recommended hole diameter is
be less suitable than abrasive jet machining or high-speed
60 % of the maximum allowable diameter. Table 2 lists the
drilling (7).
recommended hole diameter ranges for several common strain
Since any residual stress created by the selected drilling
gage rosette types.
method will adversely affect the accuracy of results, a verifi-
NOTE 6—As the ratio D / D increases, the sensitivity of the method
cation of the selected process is recommended when no prior
increases in approximate proportion to (D / D) . In general, larger holes
experience is available. Such verification could consist of
are recommended because of the increased sensitivity.
applying a strain gage rosette, identical to the rosette used in
8.1.2 The center of the drilled hole shall coincide with the
the test, to a stress-free specimen of the same nominal
center of the strai
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