ASTM E92-23 PDF

Full title and description

ASTM E92-23 — Standard Test Methods for Vickers Hardness and Knoop Hardness of Metallic Materials. This designation defines the procedures, equipment requirements, measurement and calculation rules, and reporting practices for determining Vickers and Knoop hardness on metallic materials using diamond indenters over the standard and low‑force ranges.

Abstract

This standard provides test methods for measuring Vickers and Knoop indentation hardness of metallic materials, including guidance for units (SI with common historic gf/kgf values shown for information), test forces, indenter geometry, verification and calibration of test machines, procedures for making and measuring indentations, and the calculation and reporting of hardness values. For microindentation force ranges and additional microtesting guidance the standard cross‑references Test Method E384.

General information

• Status: Active / Current.
• Publication date: July 1, 2023 (designated E92‑23).
• Publisher: ASTM International (ASTM).
• ICS / categories: Mechanical testing of metals — ICS 77.040.10.
• Edition / version: E92‑23 (current revision).
• Number of pages: 28 pages (standard PDF length).

Scope

These test methods cover the determination of Vickers and Knoop hardness of metallic materials by applying diamond indenter geometries and measuring indentation dimensions. The standard defines required equipment (indenters, optical measurement systems), acceptable force ranges for standard/low‑force testing, measurement and averaging procedures, calculation of hardness numbers in SI units (with traditional gf/kgf values shown for information), verification/ calibration procedures for hardness testing machines, and reporting requirements. Microindentation considerations and extended microforce procedures are addressed by cross‑reference to Test Method E384.

Key topics and requirements

• Definitions and indenter geometries for Vickers (diamond square pyramid, included angle 136°) and Knoop (elongated rhombic pyramid) tests.
• Specified force ranges and conversion to SI units; historical gf/kgf units retained for guidance.
• Measurement methods: optical measurement of indentation diagonals (Vickers) or long diagonal (Knoop), rules for diagonal‑difference checks and averaging.
• Machine verification and calibration procedures, including force calibration and verification practices.
• Reporting, uncertainty, and conformance guidance (number of indents, spacing, environmental and specimen preparation notes).
• Cross‑references to related test methods for microindentation (E384) and specialized material considerations (e.g., ceramic test methods C1326/C1327).

Typical use and users

Used in metallurgical laboratories, quality control and inspection departments, research and development, heat‑treatment shops, and by standards bodies and defense agencies to evaluate hardness, material condition, and process control. The standard is suitable for routine and referee testing where Vickers or Knoop indentation hardness values are required. ASTM E92-23 is approved for use by U.S. governmental agencies including Department of Defense applications where cited.

Related standards

Commonly referenced and complementary standards include: Test Method E384 (Microindentation Hardness of Materials), E18 (Rockwell Hardness), E10 (Brinell Hardness), E4 and E74 (force and machine calibration practices), E140 (hardness conversion tables), and ceramics methods C1326/C1327 for non‑metal materials. Other ASTM test/practice references and apparatus standards are cited within E92.

Keywords

Vickers, Knoop, hardness, indentation, microindentation, hardness testing, metallic materials, calibration, ASTM E92, E92‑23.

FAQ

Q: What is this standard?

A: ASTM E92‑23 is the ASTM International standard that specifies test methods for determining Vickers and Knoop hardness of metallic materials (designation E92, 2023 revision).

Q: What does it cover?

A: It covers indenter geometry, forces and units (SI with traditional gf/kgf guidance), measurement and calculation procedures, machine verification and calibration, specimen preparation notes, and reporting requirements for Vickers and Knoop hardness testing. For microindentation (very low forces) users are referred to Test Method E384.

Q: Who typically uses it?

A: Metallurgical and materials testing laboratories, production quality/inspection teams, R&D labs, heat‑treat shops, standards committees, and government/defense organizations that require standardized hardness measurement methods.

Q: Is it current or superseded?

A: The current revision is E92‑23 (approved/published in 2023). It supersedes earlier revisions (for example E92‑16/E92‑17 editions). Users should reference E92‑23 as the active version unless a later revision has been published.

Q: Is it part of a series?

A: E92 sits within ASTM Committee E28 (Mechanical Testing) and subcommittee E28.06 on indentation hardness testing; it is frequently used alongside related hardness and microindentation standards such as E384 (microindentation), E18 (Rockwell), E10 (Brinell), and other calibration and metallography practices.

Q: What are the key keywords?

A: Vickers, Knoop, hardness, indentation, microindentation, metallic materials, test method, calibration, hardness number, ASTM E92‑23.