technique articles

Several Factors Affecting the Measurement Accuracy of Webster Hardness Tester


Webster hardness tester is small and portable, and it is also convenient and fast to use. It is deeply loved by quality inspection personnel of aluminum profile factories at home and abroad. Although Webster hardness tester is very simple to use, some improper operations will also bring deviation to the measurement results. Here we will talk about these factors that affect the measurement accuracy to help you use Webster hardness tester normally.

1. There are requirements for the distance between adjacent indentations.

During the test, it should be noted that the distance between two adjacent indentations should not be less than 6mm, otherwise, the previous indentation will affect the accuracy of the next measurement.

2. Pay attention to the influence of oxide film on hardness.

Although the hard oxide film is very thin, it will also affect the accuracy of hardness measurement of aluminum profile. Experience shows that the thickness is 10 μ M oxide film will make the hardness measurement value higher by 0.5 ~ 1HW.

3. The coating of profile shall be removed.

All kinds of coatings will seriously affect the measurement accuracy. Therefore, it is required to remove the coating with sandpaper or solvent before hardness measurement.