2. Testing Instrument
So far, the Webster Hardness Tester for aluminum alloy has three models: W-20, W-20a and W-20b. The testers used the most in Chinese industries are W-20 series Webster Hardness Testers which are manufactured by Shenyang TX Company. Shenyang TX has been manufacturing Webster Hardness Tester for 28 years. The product quality and test accuracy have all been up to the international advanced level. So far, the national standard for Webster hardness test which Shenyang TX participated in drafting is going to be carried out. W-20 is a general type suitable for testing aluminum alloy material whose thickness is from 0.6 to 6.0mm, especially suitable for testing aluminum alloy profiles.
W-20a can be used for testing aluminum alloy material whose thickness is from 0.6 to 13mm.
W-20b is designed specialized for thin tubes. It can be applied in testing hardness of aluminum alloy tubes with diameter more than 6.0mm.
3. Specimen
The testing surface of specimen should be smooth and clean, without any mechanical damage or burr on the edge. Any coating on the testing surface should be cleared away thoroughly, and any slight scratching should be polished lightly.
The smallest size of specimen is about 25mm×25mm. When testing, the distance from indentation to edge should be assured no less than 3mm.