GB/T 9790-2021 (English Version) PDF

Scope: This document specifies the principles, symbols and descriptions, equipment, factors affecting measurement accuracy, test procedures, uncertainty of results and test reports for Vickers and Knoop microhardness tests on metals and other inorganic coatings. This document is applicable to the determination of various coatings such as electrodeposited coatings, autocatalytic coatings, sprayed aluminum coatings and aluminum anodized coatings. When measuring, the test force is generally not greater than 9.807N (1kg f). 8.3 of this document is applicable to the determination of the microhardness of the coating section, and 8.4 is applicable to the determination of the microhardness of the coating surface. Note 1: Parts 1 to 4 of GB/T 18449 describe the Knoop hardness test for metallic materials. Parts 1 to 4 of GB/T 4340 describe the Vickers hardness test for metallic materials. GB/T 21838 (all parts) describes instrumented indentation tests for hardness and material parameters of metallic materials. Note 2: The test force of the covering layer is usually selected within the range of micro-Vickers hardness in GB/T4340.1-2009. However, since it is advisable to select as large a test force as possible, a test force within the Vickers hardness range of small and medium force values in GB/T4340.1-2009 can also be selected.

GB/T 9790-2021 Referenced Document

GB/T 18449.1-2009 Metallic materials.Knoop hardness test.Part 1:Test method
GB/T 18449.2 Metallic materials.Knoop hardness test.Part 2:Verification and calibration of testing machines
GB/T 4340.1-2009 Metallic materials.Vickers hardness test.Part 1:Test method
GB/T 4340.2 Metallic materials.Vickers hardness test.Part 2:Verification and calibration of testing machines
GB/T 4340.4 Metallic materials—Vickers hardness test—Part 4：Tables of hardness values*， 2022-03-09 Update
GB/T 6462 Metallic and oxide coatings-Measurement of coating thinckness-Microscopical method
ISO 6507-2:2005 Metallic materials - Vickers hardness test - Part 2: Verification and calibration of testing machines
JJG 1047 Verification Regulation of Metallic Knoop Hardness Testers
JJG 151 Falling Ball Resilience Modulus Tester

2021 GB/T 9790-2021 Metallic materials—Vickers and Knoop microhardness tests of metallic and other inorganic coatings
1988 GB/T 9790-1988 Metallic and related coatings--Vickers and knoop microhardness tests