GB/T 34205-2017Metallic materials—Hardness testing—Ultrasonic contact impedance method (English PDF)

1 Scope

This standard specifies the terms and definitions, principles, symbols and descriptions of the hardness test of ultrasonic contact resistance of metallic materials, test equipment, test

Sample, Test Procedure, Uncertainty of Results, Test Report.

This standard applies to metal materials ultrasonic contact resistance method hardness test is also applicable to the metal coating, coating and hardened layer ultrasonic contact resistance

Anti-method hardness test.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version applies to this article

Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 4340.1 Vickers hardness test of metallic materials - Part 1. Test methods

GB/T 4340.2 Vickers hardness test of metallic materials - Part 2. Inspection and calibration of hardness tester

GB/T 4340.3-2012 Vickers hardness test of metallic materials - Part 3. Calibration of standard hardness blocks

GB/T 10623 metallic materials mechanical properties test terms

Technical specification of ultrasonic hardness tester

JJF1436 ultrasonic hardness calibration standard

3 Terms and definitions

GB/T 10623 defined and the following terms and definitions apply to this document.

4 principle

Ultrasonic contact impedance method is a direct measurement of indentation dynamic press-in method. The end is inlaid with a specific head (such as regular pyramid diamond

Indenter) of the vibrating rod is excited to do vertical ultrasonic vibration, with a certain test force will be pressed into the test surface, the longitudinal vibration of the vibrating rod will

By the impedance, the resonant frequency changes. The amount of variation is proportional to the indentation surface area and the effective modulus of elasticity of the system,

The rate of change is obtained.