Active Standard ASTM E766 | Developed by Subcommittee: E04.11
Book of Standards Volume: 03.01
Historical (view previous versions of standard)
Significance and Use
4.1 Proper use of this practice can yield calibrated magnifications with precision of 5 % or better within a magnification range of from 10 to 50 000X.
4.2 The use of calibration specimens traceable to international/national standards, such as NIST-SRM 484, with this practice will yield magnifications accurate to better than 5 % over the calibrated range of operating conditions.
4.3 The accuracy of the calibrated magnifications, or dimensional measurements, will be poorer than the accuracy of the calibration specimen used with this practice.
4.4 For accuracy approaching that of the calibration specimen this practice must be applied with the identical operating conditions (accelerating voltage, working distance and magnification) used to image the specimens of interest.
4.5 It is incumbent upon each facility using this practice to define the standard range of magnification and operating conditions as well as the desired accuracy for which this practice will be applied. The standard operating conditions must include those parameters which the operator can control including: accelerating voltage, working distance, magnification, and imaging mode.
1.1 This practice covers general procedures necessary for the calibration of magnification of scanning electron microscopes. The relationship between true magnification and indicated magnification is a complicated function of operating conditions.2 Therefore, this practice must be applied to each set of standard operating conditions to be used.
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 and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
E7 Terminology Relating to Metallography
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
ISO StandardISOGuide30:1992 Terms and Definitions Used in Connection with Reference Materials Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
ICS Number Code 37.020 (Optical equipment)