ASTM-E8

ASTM E8/E8M – Standard Test Methods for Tension Testing of Metallic Materials

Overview

The ASTM E8/E8M tension test is performed on metallic materials in any form at room temperature. Specifically, it determines properties of metals such as yield strength, yield point elongation, tensile strength, elongation, and reduction of area. It is one of the most common test procedures performed on metal samples and one we help customers with frequently here at United.

A variety of different sample types are referenced in ASTM E8 such as Plate-Type Specimens, Sheet-Type Specimens, Round Specimens, Specimens for Sheet, Strip, Flat Wire, and Plate, Specimens for Wire, Rod, and Bar, Specimens for Rectangular Bar, Specimens for Pipe and Tube, Specimens for Forgings, Specimens for Castings, Specimen for Malleable Iron, Specimen for Die Castings and Specimens for Powder Metallurgy.

In most cases, once a customer determines which type of sample they will be testing and the dimensions of the sample as specified in ASTM E8, choosing the proper test frame and grips is a relatively simple process.

Test Frame

It must conform to requirements of ASTM E4 and be capable of testing to the forces required. All United test frames meet or exceed the ASTM E4 specification

Grips

ASTM E8/E8M references several different styles of grips depending on the type of sample being tested, including Wedge Grips, Grips for Threaded and Shouldered Specimens and Brittle Materials, Grips for Sheet Materials and Grips for Wire. United offers a complete line of grips and can help you determine which grips are most suitable for your specific test specimen when performing ASTM E8/E8M.

Extensometers

The extensometer should conform to ASTM E83. All extensometers sold by United meet this specification. Depending on the dimension of the sample you want to test, special consideration should be given to the gauge length of the extensometer you plan to use.

Specimen Preparation

This is a critical step in properly performing the ASTM E8/E8M test procedure and often the most overlooked. Improper or careless test preparation is one of the biggest causes of inconsistent test results. The different types of specimens referenced in the ASTM E8/E8M standard are Plate-Type, Sheet-Type, Strip-Type, Flat Wire Type, and Round Specimens. Given the tolerances specified in the ASTM E8/E8M standard, precision machining or cutting devices are usually required to ensure proper sample preparation. United offers several different types of sample cutters which will ensure that your test specimens are the same each time.

Test Procedure

United’s DragonFly UTS software along with one of our Universal Test Machines is fully capable of performing the ASTM E8/E8M test procedure. Each UTM we sell includes the test frame, loadcell, Windows PC, software, and the pre-written test procedure. Test speed, calculations (stress, strain, elongation, yield, tensile strength) custom reports, and many other features are available immediately upon system set-up.

Conclusion

United has done virtually all the work for our customers when it comes to performing the ASTM E8/E8M test procedure. Customers simply need to determine which sample type they will be testing so we can choose the proper capacity test frame and the correct grips.

Link to standard –  http://www.astm.org/cgi-bin/resolver.cgi?E8E8

Citation – ASTM E8 / E8M-09, Standard Test Methods for Tension Testing of Metallic Materials, ASTM International, West Conshohocken, PA, 2009, www.astm.org