Standard Test Method for Leeb Hardness Testing of Steel Products
Standard Test Method for Leeb Hardness Testing of Steel Products
SIGNIFICANCE AND USE 5.1 Hardness of a material is a poorly defined term that may have many meanings depending on the type of test performed and the expectations of the person involved. The Leeb hardness test is of the dynamic or rebound type, which primarily depends both on the plastic and on the elastic properties of the material being tested. The results obtained are indicative of the strength and dependent on the heat treatment of the material tested. 5.2 The Leeb hardness test is a superficial determination only measuring the condition of the surface contacted. The results generated at that location do not represent the part at any other surface location and yield no information about the material at subsurface locations. SCOPE 1.1 This test method covers the determination of the Leeb hardness of steel, cast steel, and cast iron (Part A), including the methods for the verification of Leeb hardness testing instruments (Part B), and the calibration of standardized test blocks (Part C). Note 1: The original title of this standard was “Standard Test Method for Equotip Hardness Testing of Steel Products.”1 1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. 1.3 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ASTM A956/A956M-22 is the Standard Test Method for Leeb Hardness Testing of Steel Products. Developed by ASTM International, this standard specifies a dynamic or rebound testing method, known as the Leeb hardness test, for determining the surface hardness of steel, cast steel, and cast iron products. The standard offers guidance for the correct use of Leeb hardness instruments, procedures for verifying their performance, and calibration of standardized hardness test blocks. This method is widely respected for its speed and non-destructive nature, making it highly suitable for both production environments and quality assurance processes.
The Leeb hardness test primarily reflects both plastic and elastic properties of the tested material, serving as an indicator of material strength, and is sensitive to the heat treatment status of steel products. It is important to note that the Leeb method only measures the surface condition at the tested location and does not provide information about subsurface or other areas of the component.
Другие стандарты ASTM
The Leeb hardness testing method, as described in ASTM A956/A956M-22, finds significant use in industrial and quality control processes, offering several practical advantages:
For organizations and professionals seeking comprehensive hardness evaluation practices, ASTM A956/A956M-22 integrates with several other key standards:
Adhering to ASTM A956/A956M-22 ensures robust, consistent, and internationally recognized procedures for dynamic hardness testing of steel products, supporting quality, safety, and regulatory compliance in various industrial settings.
Keywords: Leeb hardness, rebound hardness test, dynamic hardness testing, ASTM A956, steel hardness, non-destructive testing, quality control, hardness calibration, surface hardness test.