ASTM E8/E8M-21 - 1.2.2021
 
Significance and Use

4.1?Tension tests provide information on the strength and ductility of materials under uniaxial tensile stresses. This information may be useful in comparisons of materials, alloy development, quality control, and design under certain circumstances.

4.2?The results of tension tests of specimens machined to standardized dimensions from selected portions of a part or material may not totally represent the strength and ductility properties of the entire end product or its in-service behavior in different environments.

4.3?These test methods are considered satisfactory for acceptance testing of commercial shipments. The test methods have been used extensively in the trade for this purpose.

 
1. Scope

1.1?These test methods cover the tension testing of metallic materials in any form at room temperature, specifically, the methods of determination of yield strength, yield point elongation, tensile strength, elongation, and reduction of area.

1.2?The gauge lengths for most round specimens are required to be 4D for E8 and 5D for E8M. The gauge length is the most significant difference between E8 and E8M test specimens. Test specimens made from powder metallurgy (P/M) materials are exempt from this requirement by industry-wide agreement to keep the pressing of the material to a specific projected area and density.

1.3?Exceptions to the provisions of these test methods may need to be made in individual specifications or test methods for a particular material. For examples, see Test Methods and Definitions A370 and Test Methods B557, and B557M.

1.4?Room temperature shall be considered to be 10 to 38?C [50 to 100?F] unless otherwise specified.

1.5?The values stated in SI units are to be regarded as separate from inch/pound units. The values stated in each system are not exact equivalents; therefore each system must be used independently of the other. Combining values from the two systems may result in non-conformance with the 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.7?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.

 
2. Referenced Documents

B557M-15(2023)

Standard Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products (Metric)

E4-21

Standard Practices for Force Calibration and Verification of Testing Machines

E6-23a

Standard Terminology Relating to Methods of Mechanical Testing (Includes all amendments and changes 3/29/2023).

E29-22

Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

A356/A356M-21

Standard Specification for Steel Castings, Carbon, Low Alloy, and Stainless Steel, Heavy-Walled for Steam Turbines

A370-23

Standard Test Methods and Definitions for Mechanical Testing of Steel Products

E1856-13(2021)

Standard Guide for Evaluating Computerized Data Acquisition Systems Used to Acquire Data from Universal Testing Machines

E2658-15(2023)

Standard Practices for Verification of Speed for Material Testing Machines

E83-23

Standard Practice for Verification and Classification of Extensometer Systems

E345-24

Standard Test Methods of Tension Testing of Metallic Foil

E691-23

Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

E1012-19

Standard Practice for Verification of Testing Frame and Specimen Alignment Under Tensile and Compressive Axial Force Application

D1566-21a

Standard Terminology Relating to Rubber (Includes all amendments and changes 11/10/2021).

B557-15(2023)

Standard Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products