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ASTM E3070-22e1

(Test Method)

Standard Test Method for Shear Thinning Index of Non-Newtonian Liquids Using a Rotational Viscometer

Standard Test Method for Shear Thinning Index of Non-Newtonian Liquids Using a Rotational Viscometer

SIGNIFICANCE AND USE
5.1 The flow behavior of many fluids of interest is non-Newtonian in nature. Non-Newtonian behavior is best studied using rheometry apparatus. Nonetheless, estimations on non-Newtonian behavior may be made by recording viscosity at differing rotational speeds (or shear rates) using rotational viscometers.  
5.2 The shear thinning index provides a tool for the estimation of the amount of non-Newtonian behavior.  
5.3 The shear thinning index may be used in quality assessment, trouble shooting, specification acceptance, and research.
SCOPE
1.1 This test method describes the determination of the shear thinning index of a shear-rate dependent (non-Newtonian) fluid using a rotational viscometer. A value of the shear thinning index of unity indicates that the material is Newtonian in behavior. A value greater than unity indicates shear thinning behavior.  
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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 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.

General Information

Status
Published
Publication Date
31-Dec-2021
ICS
17.060 - Measurement of volume, mass, density, viscosity
Technical Committee
E37 - Thermal Measurements
Drafting Committee
E37.08 - Rheology
Current Stage
Ref Project

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ASTM E3070-22e1 - Standard Test Method for Shear Thinning Index of Non-Newtonian Liquids Using a Rotational ViscometerASTM E3070-22e1 - Standard Test Method for Shear Thinning Index of Non-Newtonian Liquids Using a Rotational Viscometer
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ASTM E3070-22e1 - Standard Test Method for Shear Thinning Index of Non-Newtonian Liquids Using a Rotational Viscometer
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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.
´1
Designation: E3070 − 22
Standard Test Method for
Shear Thinning Index of Non-Newtonian Liquids Using a
1
Rotational Viscometer
This standard is issued under the fixed designation E3070; 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
ε NOTE—Added research report footnote to Section 12 editorially in February 2022.
1. Scope* 3. Terminology
3.1 Definitions—Specific technical terms used in this stan-
1.1 This test method describes the determination of the
dard method are described in Terminologies E473 and E1142
shear thinning index of a shear-rate dependent (non-
including Celsius, non-Newtonian, rheometry, viscosity, and
Newtonian) fluid using a rotational viscometer. A value of the
viscometer.
shear thinning index of unity indicates that the material is
3.2 Definitions of Terms Specific to This Standard:
Newtonian in behavior. A value greater than unity indicates
3.2.1 shear thinning, n—a decrease in viscosity with in-
shear thinning behavior.
creasing shear rate.
1.2 The values stated in SI units are to be regarded as
3.2.2 shear thinning index, n—the ratio of apparent viscos-
standard. No other units of measurement are included in this
ity at two rotational speeds or shear rates.
standard.
1.3 This standard does not purport to address all of the
4. Summary of Test Method
safety concerns, if any, associated with its use. It is the
4.1 For Newtonian fluids, viscosity is independent of shear
responsibility of the user of this standard to establish appro-
rate. Non-Newtonian fluids are those for which the viscosity
priate safety, health, and environmental practices and deter-
changes as a function of shear rate. Many materials of interest
mine the applicability of regulatory limitations prior to use.
are non-Newtonian in behavior.
1.4 This international standard was developed in accor-
4.2 The viscosity of a non-Newtonian fluid is measured at
dance with internationally recognized principles on standard-
different shear rates and the values compared as their ratio.
ization established in the Decision on Principles for the
This is known as the shear thinning index. For Newtonian
Development of International Standards, Guides and Recom-
fluids the shear thinning ratio is unity. For non-Newtonian
mendations issued by the World Trade Organization Technical
fluids the shear thinning ratio increases with increasing non-
Barriers to Trade (TBT) Committee.
Newtonian nature.
2. Referenced Documents
4.3 The shear thinning index of non-Newtonian fluids is
2
determined by the ratio of viscosity measurements made at two
2.1 ASTM Standards:
rotational speeds, preferably a decade apart.
E473 Terminology Relating to Thermal Analysis and Rhe-
ology
NOTE 1—The shear thinning index depends upon experimental condi-
E1142 Terminology Relating to Thermophysical Properties tions including geometry and rotational speed. These values shall be
reported.
E2975 Test Method for Calibration or Calibration Verifica-
tion of Concentric Cylinder Rotational Viscometers
5. Significance and Use
5.1 The flow behavior of many fluids of interest is non-
1 Newtonian in nature. Non-Newtonian behavior is best studied
ThistestmethodisunderthejurisdictionofASTMCommitteeE37onThermal
Measurements and is the direct responsibility of Subcommittee E37.08 on Rheol-
using rheometry apparatus. Nonetheless, estimations on non-
ogy.
Newtonian behavior may be made by recording viscosity at
Current edition approved Jan. 1, 2022. Published January 2022. Originally
differing rotational speeds (or shear rates) using rotational
approved in 2018 as E3070 – 18. DOI: 10.1520/E3070-22E01.
2
viscometers.
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
5.2 The shear thinning index provides a tool for the estima-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. tion of the amount of non-Newtonian behavior.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
´1
E3070 − 22
5.3 The shear thinning index may be used in quality 8. Procedure – Determination of Non-Newtonian
assessment, trouble shooting, specification acceptance, and Behavior and Selection of Experimental Conditions
research.
8.1 Sele
...

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1.4 Proper safety and hygiene precautions must be taken when working with pesticide formulations to prevent skin or eye contact, vapor inhalation, and environmental contamination. Read and follow all handling instructions for the specific formulation and conduct the test in accordance with good laboratory practice.
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1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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