How to use Rockwell hardness tester correctly?

1. When replacing the indenter or anvil, the contact parts should be kept clean. After replacement, use a steel sample of a certain hardness to test several times until the hardness values obtained twice in a row are the same.

The purpose is to press the contact part between the indenter or anvil and the testing machine tightly and ensure good contact, so as not to affect the accuracy of the test results.

2. The hardness tester itself will produce two kinds of errors. One is the error caused by the deformation and movement of its parts; the other is the error caused by the hardness parameters exceeding the prescribed standards.

For the second type of error, the hardness tester needs to be calibrated with a standard block before measurement. For the Rockwell hardness tester calibration results, the difference is qualified within ±1. A stable value with a difference within ±2 can give a correction value. When the difference is outside the range of ±2, the hardness meter must be calibrated and repaired or other hardness testing methods must be used.

3. Before loading, check whether the loading handle is in the unloading position. Normally iqualitrol Rockwell testers equips metal loading handle. When loading, the movement should be gentle and steady, and do not use too much force. After loading, the loading handle should be placed in the unloading position to prevent the instrument from being under load for a long time and causing plastic deformation, which will affect the measurement accuracy.

4. For specimens with complex shapes, cushion blocks of corresponding shapes should be used and fixed before testing. Round specimens are generally placed in a V-shaped groove for testing.

5. Instrument maintenance: After the hardness tester is adjusted, when starting to measure the hardness, the first test point is not used. Because of fear of poor contact between the sample and the anvil, the measured value will be inaccurate. After the first point test is completed and the hardness tester is in the normal operating mechanism, the sample is formally tested and the measured hardness value is recorded.

6. When the test piece allows, it is generally recommended to test at least three hardness values in different parts and take the average value as the hardness value of the test piece.