Huayin hardness testerBrinell hardness tester indenter Rockwell hardness tester indenter HB indenter Brinell indenter Vickers hardness tester indenter

1Deviation of the shape and size of the indenter from the defined value

If the diameter of the indenter steel ball used in the Brinell test is large or the angle between the two opposing sides of the indenter used in the paper test is too large, the indentation will be large and the resulting hardness will be falsely low. For the Rockwell test, if the diameter of the steel ball is too large or the cone angle of the diamond indenter is too large, when it is pressed against the specimen, the contact area increases, the resistance also increases, and the indentation depth decreases, causing the hardness value to deviate.
2. Ellipticity of steel ball indenter
If the steel ball indenter is an elliptical ball, when the copper ball is pressed into the specimen in the long glaze direction, the indentation is small and the hardness value is high for the Brinell test, while for the Rockwell test, due to the small contact area and low resistance, the indentation is deep and the hardness value is low. On the contrary, when the steel ball is pressed into the specimen in the short pull direction, the hardness value is lower for the Brinell test and higher for the Rockwell test.
3. The hardness of the indenter is not high enough
If the hardness of the indenter is not high enough, it will deform itself when it is pressed against the specimen, which will cause the indentation hardness to be lower in the Brinell and Shore tests. For the Rockwell test, the contact area between the indenter and the specimen increases, and the indentation depth decreases, resulting in a higher ratio.
4. The surface smoothness of the pressure head does not meet the requirements
If the surface smoothness of the indenter is not high, it will increase the resistance during pressing, and for cloth and Vickers tests, the indentation will decrease; For the Rockwell test, reducing the indentation depth will result in a higher hardness value.