استاندارد ASTM E18
در خصوص انجام تست سختی سنجی مواد فلزی
در مقیاس راکول
نسخه 2012
37 صفحه
Scope
1.1 These test methods cover the determination of the
Rockwell hardness and the Rockwell superficial hardness of
metallic materials by the Rockwell indentation hardness principle. This standard provides the requirements for Rockwell
hardness machines and the procedures for performing Rockwell hardness tests.
1.2 This standard includes additional requirements in annexes:
Verification of Rockwell Hardness Testing Machines Annex A1
Rockwell Hardness Standardizing Machines Annex A2
Standardization of Rockwell Indenters Annex A3
Standardization of Rockwell Hardness Test Blocks Annex A4
Guidelines for Determining the Minimum Thickness of a Test Piece Annex A5
Hardness Value Corrections When Testing on Convex
Cylindrical Surfaces
Annex A6
1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test.
List of ASTM Standards Giving Hardness Values
Corresponding
to Tensile Strength Appendix X1
Examples of Procedures for Determining Rockwell
Hardness Uncertainty Appendix X2
1.4 Units—At the time the Rockwell hardness test was
developed, the force levels were specified in units of
kilograms-force (kgf) and the indenter ball diameters were
specified in units of inches (in.). This standard specifies the
units of force and length in the International System of Units
(SI); that is, force in Newtons (N) and length in millimeters
(mm). However, because of the historical precedent and
continued common usage, force values in kgf units and ball diameters in inch units are provided for information and much
of the discussion in this standard refers to these units.
1.5 The test principles, testing procedures, and verification procedures are essentially identical for both the Rockwell and Rockwell superficial hardness tests. The significant differences
between the two tests are that the test forces are smaller for the
Rockwell superficial test than for the Rockwell test. The same type and size indenters may be used for either test, depending
on the scale being employed. Accordingly, throughout this
standard, the term Rockwell will imply both Rockwell and Rockwell superficial unless stated otherwise.
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 and health practices and determine the applicability of regulatory limitations prior to use.
امتحانات هماهنگ پیش دانشگاهی - فیزیک علوم تجربی - دی ماه سه سال گذشته (91 تا 93) - با پاسخ تشریحی
