ASTM E436 - 03 (2021)

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Designation: E436 −03 (Reapproved 2021)

Standard Test Method for

Drop-Weight Tear Tests of Ferritic Steels

This standard is issued under the ﬁxed designation E436; 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 (´) indicates an editorial change since the last revision or reapproval.

1. Scope

1.1 This test method covers drop-weight tear tests (DWTT)

on ferritic steels with thicknesses between 3.18 mm and 19.1

mm.

1.2 The values stated in SI units are to be regarded as

standard. No other units of measurement are included in this

standard.

1.3 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 appro-

priate safety, health, and environmental practices and deter-

mine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accor-

dance with internationally recognized principles on standard-

ization established in the Decision on Principles for the

Development of International Standards, Guides and Recom-

mendations issued by the World Trade Organization Technical

Barriers to Trade (TBT) Committee.

2. Referenced Documents

2.1 ASTM Standards:

E208 Test Method for Conducting Drop-Weight Test to

Determine Nil-Ductility Transition Temperature of Fer-

ritic Steels

E1823 Terminology Relating to Fatigue and Fracture Testing

3. Terminology

3.1 Terminology E1823 is applicable to this test method.

4. Signiﬁcance and Use

4.1 This test method can be used to determine the appear-

ance of propagating fractures in plain carbon or low-alloy pipe

steels (yield strengths less than 825 MPa) over the temperature

range where the fracture mode changes from brittle (cleavage

or ﬂat) to ductile (shear or oblique).

4.2 This test method can serve the following purposes:

4.2.1 For research and development, to study the effect of

metallurgical variables such as composition or heat treatment,

or of fabricating operations such as welding or forming on the

mode of fracture propagation.

4.2.2 For evaluation of materials for service to indicate the

suitability of a material for speciﬁc applications by indicating

fracture propagation behavior at the service temperature(s).

4.2.3 For information or speciﬁcation purposes, to provide a

manufacturing quality control only when suitable correlations

have been established with service behavior.

5. Apparatus

5.1 The testing machine shall be either a pendulum type or

a vertical-dropped-weight (Note 1) type. The machine shall

provide sufficient energy to completely fracture a specimen in

one impact.

5.1.1 As a guide in the design of the equipment it has been

found that up to 2712 J of energy may be required to

completely fracture specimens of steel up to 12.7 mm in

thickness with tensile strengths to 690 MPa.

NOTE 1—Equipment of the vertical-dropped-weight variety that can be

readily modiﬁed to conduct the drop-weight tear test is described in Test

Method E208.

NOTE 2—Current pipeline grade steels take more thn 4kJ at design

temperature of -5 °C

5.2 The specimen shall be supported in a suitable manner to

prevent sidewise rotation of the specimen.

5.3 The velocity of the hammer (in either type of testing

machine) shall be not less than 4.88 m/s.

6. Test Specimen

6.1 The test specimen shall be a 76.2 mm by 305 mm by

full-plate-thickness edge-notch bend specimen employing a

pressed notch. Fig. 1 presents the dimensions and tolerances of

the specimens. The specimens shall be removed from the

material under test by sawing, shearing, or ﬂame cutting, with

or without machining.

NOTE 3—If the specimen is ﬂame cut it is usually difficult to press in the

notch unless the heat-affected zone is removed by machining.

This method is under the jurisdiction of ASTM Committee E08 on Fatigue and

Fracture and is the direct responsibility of Subcommittee E08.02 on Standards and

Terminology.

Current edition approved June 1, 2021. Published June 2021. Originally

approved in 1971. Last previous edition approved 2014 as E436–03(2014). DOI:

10.1520/E0436-03R21.

For referenced ASTM standards, visit the ASTM website, www.astm.org, or

contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM

Standards volume information, refer to the standard’s Document Summary page on

the ASTM website.

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the

Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

6.2 The notch shall be pressed to the depth shown in Fig. 1

with a sharp tool-steel chisel with an included angle of 45° 6

2°. Machined notches are prohibited.

NOTE 4—The notch radius obtained with a sharp tool-steel chisel is

normally between 0.013 mm to 0.025 mm. When many specimens are to

be tested, it is helpful to use a jig that will guide the chisel and stop it at

the proper depth.

7. Procedure

7.1 In the temperature range from − 73 °C to 100 °C em-

ploy the procedure described in 7.1.1 and 7.1.2.

7.1.1 Completely immerse the specimens in a bath of

suitable liquid at a temperature within 61 °C of the desired test

temperature for a minimum time of 15 min prior to testing.

Separate the specimens by a distance at least equal to the

thickness of the specimen. Make provision for circulation of

the bath to assure uniform bath temperature.

NOTE 5—Alternatively, other methods of heating and cooling may be

used, provided they produce equivalent time at temperature of the

specimens.

7.1.2 Remove the specimens from the bath and break as

described herein within a time period of 10 s. If the specimens

are held out of the bath longer than 10 s return them unbroken

to the bath for a minimum of 10 min. Do not handle the

specimen in the vicinity of the notch by devices the tempera-

ture of which is appreciably different from the test temperature.

7.2 For temperatures outside of the range speciﬁed in 7.1

maintain the specimen temperature at the time of impact within

4 °C of the desired test temperature.

7.3 Insert the specimen in the testing machine so that the

notch in the specimen lines up with the centerline of the tup on

the hammer within 1.59 mm. Also, center the notch in the

specimen between the supports on the anvil.

7.4 Consider tests invalid if the specimen buckles during

impact.

NOTE 6—Buckling has been experienced with specimen thicknesses

less than 4.75 mm.

8. Specimen Evaluation

8.1 For the purposes of this method, shear-fracture surfaces

shall be considered as those having a dull gray silky appear-

ance which are commonly inclined at an angle to the specimen

surface. Cleavage or brittle fractures shall be considered those

that are bright and crystalline in appearance and that are

perpendicular to the plate surface. The cleavage fractures

generally extend from the root of the notch and are surrounded

by a region of shear or shear lips on the specimen surface.

8.2 Evaluate the specimens (Note 7) by determining the

percent shear area of the fracture surface neglecting the

fracture surface for a distance of one specimen thickness from

the root of the notch and the fracture surface for a distance of

one specimen thickness from the edge struck by the hammer.

Fig. 2 illustrates in the cross-hatched area that portion of the

fracture surface to be considered in the evaluation of the

percent shear area of the fracture surface.

NOTE 7—If the specimens are to be preserved for some length of time

after evaluation of the shear area or if a considerable time elapses between

testing and evaluation, the fracture surfaces should be treated to keep them

from corroding.

8.3 Occasionally specimens will exhibit the fracture appear-

ance shown in Fig. 3. On specimens of this type the fracture

appears to have stopped and started a number of times

exhibiting intermittent regions of shear and cleavage in the

midthickness portion of the specimen. The shear area included

in the rating of specimens of this type shall be that shown in the

cross-hatched area of Fig. 3 (neglect the shear areas in the

region of intermittent shear and cleavage fracture in rating the

specimen).

FIG. 1 Drop-Weight Tear Test Specimens and Support Dimensions and Tolerances (for Specimens

⁄

in. to

⁄

in. in Thickness)

FIG. 2 Fracture Surface Included in Shear-Area Determination

FIG. 3 Alternative Shear-Cleavage Fracture Appearance

E436 − 03 (2021)

8.4 For referee method of determining the percent shear

area of the fracture surface, measure the cleavage area of the

fracture surface with a planimeter on a photograph or optical

projection of the fracture surface. Then divide the cleavage

area by the net area of the specimen included in the rating,

express as percent, and subtract from 100. Alternative methods

more adaptable to routine rating are described in 8.4.1 – 8.4.3.

8.4.1 The percent shear area can be evaluated by comparing

the fracture surfaces with a calibrated set of photographs of

previously fractured specimens or with actual specimens of

calibrated percent shear areas for a speciﬁc thickness. Calibrate

in accordance with 8.4.

8.4.2 The percent shear area can be evaluated with the

procedure described in Annex A1.

8.4.3 The percent shear area can be evaluated with any other

procedure that has been demonstrated to produce results

equivalent to those obtained in 8.4.

8.5 Fig. 4 shows ﬁve DWTT specimens that have been

tested over the temperature range from − 17 °C to 16 °C . The

bright regions of the fracture are the cleavage fracture areas

and the darker gray regions are the areas of shear fracture.

(Note that the specimen tested at 4 °C has almost 100 % shear

area and it has a fracture surface that in section has shear lips

on each surface with a region of ﬂat ﬁbrous shear at the

midthickness (see Section A–A of Fig. A1.1(a)). This fracture

appearance is typical of a full shear fracture and is easily

distinguished from the ﬂat cleavage fracture in the center of the

specimen with shear lips at the specimen surfaces.

9. Report

9.1 A report of the test results shall be furnished to the

purchaser and shall include as a minimum the specimen

orientation in product (transverse or longitudinal), thickness,

heat number, material speciﬁcation, test temperature, and the

fracture appearance (percent shear area) of each specimen. If a

series of specimens is broken over a range of temperatures, a

plot of the results as percent shear area versus temperature is

desirable.

10. Precision and Bias

10.1 Precision—It is not practicable to specify the precision

of the procedure in Test Method E436 for measuring the

fracture appearance (percent shear area) as the available data

are not of a type that permits a meaningful analysis.

10.2 Bias—There is no accepted “standard” value for the

percent shear area of any material. In the absence of such a true

value, no meaningful statement can be made concerning bias of

data.

11. Keywords

11.1 brittle fracture; drop-weight tear test; ferritic steels;

fracture appearance; impact loading; percent shear area

FIG. 4 DWTT Fracture Appearances

E436 − 03 (2021)

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摘要：

ASTM E436 - 03 (2021) 是一项由美国材料与试验协会（ASTM）制定的标准试验方法，全称为“铁素体钢的落重冲击试验标准方法”，主要用于测定铁素体钢在动态加载条件下的过渡温度特性及其抗断裂性能。该标准采用落锤式冲击装置，通过对预制裂纹的试样进行单次冲击，评估钢材在低温或特定温度下的断裂韧性，特别适用于管道、压力容器及结构用钢的脆性断裂风险评估。2021年的版本确认了原有2003年标准的技术内容，确保其与当前工业实践保持一致。该标准在石油化工、能源、桥梁及重型机械等领域中具有广泛应

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ASTM E436 - 03 (2021)

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