ASTM E915-21
Standard Practice for Verifying the Alignment of X-Ray Diffraction Instruments for Residual Stress Measurement

Standard No.

ASTM E915-21

Release Date

2021

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM E915-21

Scope

1.1 This practice describes the procedure for verifying the alignment of X-ray diffraction instruments used for residual stress measurements. 1.2 This practice further describes the use of iron powder for fabrication of a stress-free test specimen to be used to quantify the systematic error that can occur in residual stress measurement of ferritic or martensitic steels. This practice is easily adapted to other alloys and ceramics by the use of a powder having a similar diffraction angle to the material to be measured. 1.3 This practice is applicable to all X-ray diffraction instruments that measure diffracted X-rays from the crystal structure of a polycrystalline specimen. It is applicable to the acceptable multiple exposure techniques of residual stress measurement as defined in Test Method E2860. Through measurement of a high-angle back-reflection set of planes, these techniques are used to derive the interatomic spacing (d-spacing) and the crystallographic strain, and then calculate residual stress in which the θ, 2θ, and ψ rotation axes can be made to coincide (see Fig. 1). 1.4 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.5 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. 1.6 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.

ASTM E915-21 Referenced Document

• ASTM E1426 Standard Test Method for Determining the Effective Elastic Parameter for X-Ray Diffraction Measurements of Residual Stress
• ASTM E177 Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• ASTM E2860 Standard Test Method for Residual Stress Measurement by X-Ray Diffraction for Bearing Steels
• ASTM E6 Standard Terminology Relating to Methods of Mechanical Testing

ASTM E915-21 history

• 2021 ASTM E915-21 Standard Practice for Verifying the Alignment of X-Ray Diffraction Instruments for Residual Stress Measurement
• 2019 ASTM E915-19 Standard Test Method for Verifying the Alignment of X-Ray Diffraction Instrumentation for Residual Stress Measurement
• 2016 ASTM E915-16 Standard Test Method for Verifying the Alignment of X-Ray Diffraction Instrumentation for Residual Stress Measurement
• 2010 ASTM E915-10 Standard Test Method for Verifying the Alignment of X-Ray Diffraction Instrumentation for Residual Stress Measurement
• 1996 ASTM E915-96(2002) Standard Test Method for Verifying the Alignment of X-Ray Diffraction Instrumentation for Residual Stress Measurement
• 1996 ASTM E915-96 Standard Test Method for Verifying the Alignment of X-Ray Diffraction Instrumentation for Residual Stress Measurement