ASTM E384

Hardness tests have been found to be very useful for materials evaluation, quality control of manufacturing processes and research and development efforts. Hardness, although empirical in nature, can be correlated to tensile strength for many metals, and is an indicator of wear resistance and ductility.

Microindentation tests extend hardness testing to materials too thin or too small for macroindentation tests. Microindentation tests allow specific phases or constituents and regions or gradients too small for macroindentation testing to be evaluated.

Because the microindentation hardness will reveal hardness variations that may exist within a material, a single test value may not be representative of the bulk hardness.

1. Scope

1.1 This test method covers determination of the microindentation hardness of materials, the verification of microindentation hardness testing machines, and the calibration of standardized test blocks.

1.2 This test method covers microindentation tests made with Knoop and Vickers indenters under test forces in the range from 9.8 × 10^-3 to 9.8 N ( 1 to 1000 gf ).

1.3 This test method includes an analysis of the possible sources of errors that can occur during microindentation testing and how these factors affect the accuracy, repeatability, and reproducibility of test results.

Note 1—While Committee E04 is primarily concerned with metals, the test procedures described are applicable to other materials.

1.4 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

C1326 Test Method for Knoop Indentation Hardness of Advanced Ceramics
C1327 Test Method for Vickers Indentation Hardness of Advanced Ceramics
E122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or Process
E140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, and Scleroscope Hardness
E175 Terminology of Microscopy
E3 Guide for Preparation of Metallographic Specimens
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E7 Terminology Relating to Metallography
E766 Practice for Calibrating the Magnification of a Scanning Electron Microscope

Index Terms

hardness; indentation; Knoop; microindentation; Vickers; Metals and metallic materials; Repeatability/reproducibility (RR); Structural metals/alloys; Verification; Vickers hardness (HV); Abb´e-Nelson illumination; Calibration--metals/alloys analysis instrumentation; Hardness (indentation)--microhardness; Indenter geometry; Knoop hardness (HK) number; Kohler illumination; Metallic hardness; ICS Number Code 19.060 (Mechanical testing)

Citing ASTM Standards

[Back to Top]