【astm標(biāo)準(zhǔn)】e 384 - 11e1

1、Designation: E384 ? 11´1Standard Test Method for Knoop and Vickers Hardness of Materials1This standard is issued under the fixed designation E384; the number immediately following the designation indicates the year

2、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 revi

3、sion or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.ε1 NOTE—Sections 8.3 and A1.1.4 were editorially corrected in March 2012.1. Scope*1.1 This test method covers deter

4、mination of the Knoop and Vickers hardness of materials, the verification of Knoop and Vickers hardness testing machines, and the calibration of standardized Knoop and Vickers test blocks.1.2 This test method covers Knoo

5、p and Vickers hardness tests made utilizing test forces in micro (9.807 × 10-3 to 9.807 N ) ( 1 to 1000 gf ) and macro (>9.807 to 1176.80 N) ( >1kg to 120 kgf ) ranges.NOTE 1—Previous versions of this standard

6、 limited test forces to 9.807 N (1 kgf).1.3 This test method includes all of the requirements to perform macro Vickers hardness tests as previously defined in Test Method E92, Standard Test Method for Vickers Hardness Te

7、sting.1.4 This test method includes an analysis of the possible sources of errors that can occur during Knoop and Vickers testing and how these factors affect the accuracy, repeatability, and reproducibility of test resu

8、lts.NOTE 2—While Committee E04 is primarily concerned with metals, the test procedures described are applicable to other materials.1.5 Units—When Knoop and Vickers hardness tests were developed, the force levels were spe

9、cified in units of grams- force (gf) and kilograms-force (kgf). 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 mm or µm.

10、However, because of the historical precedent and contin- ued common usage, force values in gf and kgf units are provided for information and much of the discussion in this standard as well as the method of reporting the

11、test results refers to these units.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 appro- pria

12、te safety and health practices and determine the applica- bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C1326 Test Method for Knoop Indentation Hardness of Advanced CeramicsC132

13、7 Test Method for Vickers Indentation Hardness of Advanced CeramicsE3 Guide for Preparation of Metallographic Specimens E7 Terminology Relating to Metallography E29 Practice for Using Significant Digits in Test Data to D

14、etermine Conformance with SpecificationsE74 Practice of Calibration of Force-Measuring Instruments for Verifying the Force Indication of Testing MachinesE92 Test Method for Vickers Hardness of Metallic Materials(Withdraw

15、n 2010)3E122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or ProcessE140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness,

16、 Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, Sclero- scope Hardness, and Leeb HardnessE175 Terminology of Microscopy E177 Practice for Use of the Terms Precision and Bias in ASTM Test Metho

17、dsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodE766 Practice for Calibrating the Magnification of a Scan- ning Electron Microscope1 This test method is under the jurisd

18、iction of ASTM Committee E04 on Metallography and is the direct responsibility of Subcommittee E04.05 on Micro- indentation Hardness Testing.With this revision the test method was expanded to include the requirements pre

19、viously defined in E28.92, Standard Test Method for Vickers Hardness Testing of Metallic Material that was under the jurisdiction of E28.06 Current edition approved Aug. 1, 2011. Published August 2011. Originally approve

20、d in 1969. Last previous edition approved in 2010 as E384 – 10 ε2. DOI: 10.1520/E0384-11E01.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For

21、 Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website. 3 The last approved version of this historical standard is referenced on www.astm.org.*A Summary of Ch

22、anges section appears at the end of this standardCopyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 Hardness tests have bee

23、n found to be very useful for materials evaluation, quality control of manufacturing pro- cesses and research and development efforts. Hardness, al- though empirical in nature, can be correlated to tensile strength for m

24、any metals, and is an indicator of wear resistance and ductility.4.2 Microindentation hardness tests extend testing to mate- rials that are too thin or too small for macroindentation hardness tests. Microindentation hard

25、ness tests also allow specific phases or constituents and regions or gradients too small for macroindentation hardness testing to be evaluated.4.3 Because the Knoop and Vickers hardness will reveal hardness variations th

26、at may exist within a material, a single test value may not be representative of the bulk hardness.4.4 The Vickers indenter usually produces a geometrically similar indentation at all test forces. Except for tests at ver

27、y low forces that produce indentations with diagonals smaller than about 25 µm, the hardness number will be essentially the same as produced by Vickers machines with test forces greater than 1 kgf, as long as the ma

28、terial being tested is reasonably homogeneous. For isotropic materials, the two diagonals of a Vickers indentation are equal in size. Recommendations for low force microindentation testing can be found in Appendix X5.4.5

29、 The Knoop indenter does not produce a geometrically similar indentation as a function of test force. Consequently, the Knoop hardness will vary with test force. Due to its rhombic shape, the indentation depth is shallow

30、er for a Knoop indentation compared to a Vickers indentation under identical test conditions. The two diagonals of a Knoop indentation are markedly different. Ideally, the long diagonal is 7.114 times longer than the sho

31、rt diagonal, but this ratio is influenced byelastic recovery. Thus, the Knoop indenter is very useful for evaluating hardness gradients or thin coatings of sectioned samples.5. Principle of Test5.1 In this test method, a

32、 Knoop or Vickers hardness number is determined based on the formation of a relatively small indentation made in the test surface of samples being evalu- ated.5.2 A Knoop or Vickers indenter, made from diamond of specifi

33、c geometry, is pressed into the test specimen surface by an accurately controlled applied force using test machines specifically designed for such work.5.3 Knoop and Vickers hardness testing is divided into micro and mac

34、ro-test force ranges as defined:Range Test Force Micro 9.807 × 10-3 to # 9.807 N ( 1 to # 1000 gf) Macro > 9.807 to # 1176.80 N ( > 1 to # 120 kgf)5.3.1 Knoop scale testing is normally performed using micro-ra

35、nge test forces (1kg and less) while the Vickers scale is used over both the micro and macro-ranges.NOTE 4—The user should consult with the manufacturer before apply- ing test forces in the macro-ranges (over 1 kg) with

36、diamond indenters previously used for micro-range testing. The diamond mount may not be strong enough to support the higher test forces and the diamond may not be large enough to produce the larger indentation sizes.5.4

37、The size of the indentation is measured using a light microscope equipped with a filar type eyepiece, or other type of measuring device (see Terminology E175). Micro-range indents are typically measured in µm (micro