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Designation: E6 – 09b´1 Standard Terminology Relating to Methods of Mechanical Testing1 This standard is issued under the fixed designation E6; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense. 1 ´ NOTE—Editorial corrections were made throughout in March 2011. 1. Scope term of interest is related to or is given below the definition for 1.1 This terminology covers the principal terms relating to the fundamental term cited. methods of mechanical testing of solids. The general defini- Term angular strain see strain tions are restricted and interpreted, when necessary, to make axial strain see strain them particularly applicable and practicable for use in stan- bending strain see strain dards requiring or relating to mechanical tests. These defini- chord modulus see modulus of elasticity direct verification see verification tions are published to encourage uniformity of terminology in compressive stress see stress product specifications. elastic constants see modulus of elasticity and Poisson’s 1.2 Terms relating to fatigue and fracture testing are defined ratio elastic modulus see modulus of elasticity in Terminology E1823. engineering strain see strain engineering stress see stress 2. Referenced Documents fracture stress see stress 2 indirect verification see verification 2.1 ASTM Standards: linear (tensile or compressive) strain see strain E8/E8M Test Methods for Tension Testing of Metallic macrostrain see strain Materials malleability see ductility 3 microstrain see strain E796 Test Method for Ductility Testing of Metallic Foil modulus of rigidity see modulus of elasticity E1823 Terminology Relating to Fatigue and Fracture Test- nominal stress see stress ing normal stress see stress 4 physical properties see mechanical properties 2.2 ISO Standard: pin see mandrel (in bend testing) ISO/IEC Guide 99:2007 International Vocabulary of plunger see mandrel (in bend testing) metrology—Basic and general concepts and terms (VIM) principal stress see stress residual strain see strain residual stress see stress 3. Index of Cross-References and Associated Definitions Rockwell superficial see Rockwell hardness number 3.1 The terms listed below are associated with terminology hardness number secant modulus see modulus of elasticity that is fundamental or commonly used. The definition for the shear strain see strain shear stress see stress static fatigue strength see creep rupture strength 1 This terminology is under the jurisdiction of ASTM Committee E28 on strain gauge fatigue life see fatigue life Mechanical Testing and is the direct responsibility of Subcommittee E28.91 on stress-rupture strength see creep rupture strength Terminology except where designated otherwise. A subcommittee designation in tangent modulus see modulus of elasticity parentheses following a definition indicates the subcommittee with responsibility for tensile stress see stress that definition. torsional modulus see modulus of elasticity Current edition approved May 15, 2009. Published June 2009. Originally torsional stress see stress approved in 1923. Last previous edition approved in 2009 as E6 – 09a. DOI: transverse strain see strain 10.1520/E0006-09B. true strain see strain 2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or true stress see stress contact ASTM Customer Service at [email protected]. For Annual Book of ASTM ultimate tensile strength (UTS) see tensile strength Standards volume information, refer to the standard’s Document Summary page on yield strength see also upper yield strength and lower the ASTM website. yield strength 3 Withdrawn. The last approved version of this historical standard is referenced on www.astm.org. 4 Available from International Organization for Standardization (ISO), 1 rue de Varembé, Case postale 56, CH-1211, Geneva 20, Switzerland, http://www.iso.ch. Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. --```,`,``,`,``,````,,`,,````,,,-`-`,,`,,`,`,,`--- Copyright ASTM International 1 Provided by IHS under license with ASTM Licensee=University of Texas Revised Sub Account/5620001114 No reproduction or networking permitted without license from IHS Not for Resale, 01/19/2014 14:02:09 MST E6 – 09b´1 4. Terminology Brinell hardness number, HB , n—result from indentation 4.1 Terms and Definitions: hardness test in which a number proportional to the quotient obtained by dividing the test force by the curved surface area accuracy, n—the permissible variation from the correct value. of the indentation which is assumed to be sphereical and of (E28.01) the diameter of the ball. alignment, n—the condition of a testing machine and load 2 2 –1 / 2 train (including the test specimen) that influences the intro- HBW 5 0.10232F/pD[D – ~D – d ! (1) duction of bending moments into a specimen during tensile where: loading. (E28.04) F = test force, N, angle of bend, n—the change in the angle between the two D = diameter of ball, mm, and legs of the specimen during a bend test, measured before d = mean diameter of the indentation, mm. release of the bending forces. DISCUSSION—In former standards, a steel ball was allowed for DISCUSSION—The angle of bend is measured before release of the hardness values below 450. In cases where a steel ball was used the bending force, unless otherwise specified. (E28.02) Brinell hardness was denoted by HB or HBS. DISCUSSION—The symbol HBW is preceded by the hardness value angle of twist (torsion test), n—the angle of relative rotation when the test is carried out under the following conditions: measured in a plane normal to the torsion specimen’s Ball diameter 10 mm longitudinal axis over the gauge length. (E28.04) Force 3000 kgf bearing area [L2], n—the product of the pin diameter and Duration of loading 10 to 15 s specimen thickness. (E28.04) When other conditions are used, the hardness value and symbol are bearing force [F], n—a compressive force on an interface. supplemented by numbers indicating the test conditions in the follow- (E28.04) ing order: diameter of ball, force, and duration of loading. (E28.06) bearing strain, n—the ratio of the bearing deformation of the Brinell hardness test, n—test in which an indenter (tungsten bearing hole, in the direction of the applied force, to the pin carbide ball) is forced into the surface of a test piece and the diameter. (E28.04) diameter of the indentation left in the surface after removal –2 bearing strength [FL ], n—the maximum bearing stress of the test force is measured. which a material is capable of sustaining. (E28.04) bearing stress [FL–2], n—the force per unit of bearing area. DISCUSSION—The tungsten carbide ball may be used for materials (E28.04) with Brinell hardness not exceeding 650. (E28.06) bearing yield strength [FL–2], n—the bearing stress at which calibration, n—a process that establishes, under specific a material exhibits a specified limiting deviation from the conditions, the relationship between values indicated by a proportionality of bearing stress to bearing strain. (E28.04) measuring system and the corresponding values indicated by bend test, n—a test for ductility performed by bending or one or more standards. folding a specimen, usually by steadily applied forces but in some instances by blows. The bending may be interrupted to DISCUSSION—This definition is intended to meet the principles of the definition of calibration provided by the ISO/IEC Guide 99:2007 examine the bent surface for cracks. International Vocabulary of Basic and General Terms in Metrology DISCUSSION—The ductility is usually judged by whether or not the (VIM). (E28.91) specimen cracks under the specified conditions of the test. calibration factor, n—the factor by which a change in DISCUSSION—There are four general types of bend tests according to the manner in which the forces are applied to the specimen to make the extensometer reading must be multiplied to obtain the bend. These are as follows: equivalent strain. 1. Free Bend DISCUSSION—For any extensometer, the calibration factor is equal to 2. Guided Bend the ratio of change in length to the product of the gauge length and the 3. Semi-Guided Bend change in extensometer reading. For direct-reading extensometers the 4. Wrap-Around Bend calibration factor is unity. (E28.01) DISCUSSION—The specimen has a substantially uniform cross-section and a length several times as great as the largest dimension of the compressive strength [FL–2], n—the maximum compressive cross-section. (E28.02) stress that a material is capable of sustaining. Compressive bias, statistical, n—a constant or systematic error in test strength is calculated by dividing the maximum force during results. (E28.04) a compression test by the original cross-sectional area of the biaxial stretching, v—a mode of sheet metal forming in which specimen. positive strains are observed in all directions at a given DISCUSSION—In the case of a material which fails in compression by location. (E28.02) a shattering fracture, the compressive strength has a very definite value. breaking force[F], n—the force at which fracture occurs. In the case of materials which do not fail in compression by a shattering fracture, the value obtained for compressive strength is an arbitrary D--```,`,``,`,``,````,,`,,````,,,-`-`,,`,,`,`,,`--- ISCUSSION—When used in connection with tension tests of thin value depending upon the degree of distortion which is regarded as materials or materials of small diameter for which it is often difficult to indicating complete failure of the material. (E28.04) distinguish between the breaking force and the maximum force developed, the latter is considered to be the breaking force.
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