With the development of materials science, Sotri's hardness tester is small in size, light in weight, no workbench, and can be used in any direction, which is convenient for on-site hardness measurement, high precision, and can also convert a variety of hardness values. Therefore, the Leeb hardness tester has been welcomed by more and more users. The Leeb hardness tester measures the factors that cause errors in hollow parts, thin plates and softer metal materials:
1. Errors caused by data conversion The error of conversion of Richter hardness to other hardness includes two aspects: one is the measurement error of the hardness of the Richter itself, which involves the dispersion of the test according to the method and the multiple models of the same type. The measurement error of the hardness tester. On the other hand, it is the error caused by the hardness measured by different hardness test methods. This is because there is no clear physical relationship between one of the various hardness test methods, and it is affected by the unreliable measurement in the comparison.
2. Errors caused by special materials The conversion table stored in the hardness tester may cause deviations for the following steel grades: all austenitic steel heat-resistant tool steels and Leysite chrome steel (tool steels) hard materials may cause elasticity. The modulus is increased so that the L value is low. This kind of steel should be tested on the cross section. Local cooling hardening will cause the L value to be high. The magnetic steel will have a low L value due to the influence of the magnetic field. Surface hardened steel, soft matrix, will lower the L value. When the hardened layer is larger than 0.8mm (0.2mm for C-type impact device), the L value will not be affected.
3. Errors in gear detection Under normal circumstances, because the tooth surface is small, the test error is relatively large. For this, the user can design the corresponding tooling according to the situation, which will help reduce the error.
4. Influence of material elasticity and plasticity In addition to the hardness and strength, the Richter value is related to the elastic modulus. The hardness value is the characteristic parameter of the hardness and plasticity of the material, because the composition of the two must be jointly determined. In the elastic part, firstly, it is obviously affected by the E modulus. In this respect, when the static hardness of the material is the same, and the E value is different, the material with a low E value has a large L value. 5. The error caused by the hot rolling direction is measured. When the workpiece is hot-rolled, if the test direction is consistent with the rolling direction, the test value will be lower due to the large elastic modulus E, so the test direction should be perpendicular to the hot rolling direction. For example, when measuring the hardness of a cylindrical section, it should be tested in the radial direction. (General cylindrical hot rolling direction is axial).
6. Influence of sample weight, roughness and thickness 7. The magnetic properties of the test piece should be less than 300 Gauss. 8. Influence of other factors When measuring the hardness of the pipe fittings, pay attention to the pipe joints. The test points should be close to the support points and parallel to the supporting force. The tube wall is thinner and a suitable core is placed in the tube.
1. Errors caused by data conversion The error of conversion of Richter hardness to other hardness includes two aspects: one is the measurement error of the hardness of the Richter itself, which involves the dispersion of the test according to the method and the multiple models of the same type. The measurement error of the hardness tester. On the other hand, it is the error caused by the hardness measured by different hardness test methods. This is because there is no clear physical relationship between one of the various hardness test methods, and it is affected by the unreliable measurement in the comparison.
2. Errors caused by special materials The conversion table stored in the hardness tester may cause deviations for the following steel grades: all austenitic steel heat-resistant tool steels and Leysite chrome steel (tool steels) hard materials may cause elasticity. The modulus is increased so that the L value is low. This kind of steel should be tested on the cross section. Local cooling hardening will cause the L value to be high. The magnetic steel will have a low L value due to the influence of the magnetic field. Surface hardened steel, soft matrix, will lower the L value. When the hardened layer is larger than 0.8mm (0.2mm for C-type impact device), the L value will not be affected.
3. Errors in gear detection Under normal circumstances, because the tooth surface is small, the test error is relatively large. For this, the user can design the corresponding tooling according to the situation, which will help reduce the error.
4. Influence of material elasticity and plasticity In addition to the hardness and strength, the Richter value is related to the elastic modulus. The hardness value is the characteristic parameter of the hardness and plasticity of the material, because the composition of the two must be jointly determined. In the elastic part, firstly, it is obviously affected by the E modulus. In this respect, when the static hardness of the material is the same, and the E value is different, the material with a low E value has a large L value. 5. The error caused by the hot rolling direction is measured. When the workpiece is hot-rolled, if the test direction is consistent with the rolling direction, the test value will be lower due to the large elastic modulus E, so the test direction should be perpendicular to the hot rolling direction. For example, when measuring the hardness of a cylindrical section, it should be tested in the radial direction. (General cylindrical hot rolling direction is axial).
6. Influence of sample weight, roughness and thickness 7. The magnetic properties of the test piece should be less than 300 Gauss. 8. Influence of other factors When measuring the hardness of the pipe fittings, pay attention to the pipe joints. The test points should be close to the support points and parallel to the supporting force. The tube wall is thinner and a suitable core is placed in the tube.
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