INVESTIGATION OF THE RATIO BETWEEN THE DYNAMIC AND STATIC HARDNESS OF METALS
Abstract
Problems of measurement of hardness by the dynamic indentation method are discussed. It is shown that an excess of dynamic hardness over static one can be described by the coefficient, which is a function of material properties and test conditions.
In framework of the dislocation theory the influence of strain rate on hardness value is shown, and the difference in ratio between static and dynamic hardness can be explained by different crystal structure of materials.With the help of the device IPM-1K the experimental diagrams of dynamic loading of various metals: steel, aluminum, bronze, brass, copper, titanium were obtained. A method of calibration of dynamic hardness testers for calculation of the Brinell hardness without using standard hardness test blocks was proposed.
In framework of the dislocation theory the influence of strain rate on hardness value is shown, and the difference in ratio between static and dynamic hardness can be explained by different crystal structure of materials.With the help of the device IPM-1K the experimental diagrams of dynamic loading of various metals: steel, aluminum, bronze, brass, copper, titanium were obtained. A method of calibration of dynamic hardness testers for calculation of the Brinell hardness without using standard hardness test blocks was proposed.
About the Authors
V. A. Rudnitsky
The Institute of Applied Physics of the National Academy of Science of Belarus
Russian Federation
D. Sc. (Engineering), Professor
Russian Federation
D. Sc. (Engineering), Professor
A. P. Kren
The Institute of Applied Physics of the National Academy of Science of Belarus
Russian Federation
D. Sc. (Engineering), Head of the mechanical testing laboratory.
Russian Federation
D. Sc. (Engineering), Head of the mechanical testing laboratory.
G. A. Lantsman
The Institute of Applied Physics of the National Academy of Science of Belarus
Russian Federation
undergraduate
Russian Federation
undergraduate
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