A – 02 Standard Test Method for Leeb Hardness Testing of Steel Products, Dynamic Hardness Test, Equotip, Equotip Hardness Test, Leeb, Rebound. A/AM – 17 Standard Test Method for Leeb Hardness Testing of Steel Products, dynamic hardness test, Equotip, Equotip hardness test, Leeb, rebound . ASTM A – Download as PDF File .pdf), Text File .txt) or read online.
|Published (Last):||4 May 2008|
|PDF File Size:||15.95 Mb|
|ePub File Size:||15.50 Mb|
|Price:||Free* [*Free Regsitration Required]|
It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
ASTM A – 12 Standard Test Method for Leeb Hardness Testing of Steel Products
ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. This disadvantage is not apparent in instruments xstm operate according to the Krautkramer rebound method. Applications on walled or impact sensitive components small measuring indentation too.
After placing the impact device on the test surface. Some astn models automatically compensate for test direction. Impact bodies show no fading even at high hardness levels compared to D device.
The results obtained are indicative of the strength and dependent on the heat treatment of the material tested. When replacement parts are used in a Leeb hardness tester it is important that they be fully compatible with the original equipment, otherwise incorrect hardness readings may be obtained. Atsm addition to the hardness. The results must therefore be correspondingly corrected. The impact and rebound velocities are assumed to be proportional to the extremal values A and B of the signal curve, which is a good approximation, if the device is constructed so, that the extremals are near the signal step caused by the impact.
Impact Device C max. Failure to provide adequate support and coupling will produce test results lower than the true hardness value. No conversions shall be employed without specific adtm between the party specifying this test method and the party performing the hardness test. Brief descriptions of the types of devices and their common applications are given in Appendix X1. Device S LS -4 -4 -4 -4 -3 -3 -3 -3 -3 -2 -2 -5 -7 -5 -8 -5 -9 -6 -6 -7 a56 -7 -8 -8 -9 Uniformity of Hardness Any instrument not meeting the requirements of Part B shall not be employed for the acceptance testing of product.
Users of this standard are expressly advised that determination of the validity of any such patent rights. The ratio of the rebound velocity to the impact velocity of the impact body is a measure of the hardness of the material under test.
Impact bodies show minimal wear even at high hardness levels when compared to D device. Applications on steel and cast steel. The quotient of these measured voltage values derived from the impact and rebound velocities, multiplied by the factor produces a number which constitutes the Leeb hardness value.
We need your help to maintenance this website. Eight laboratories tested five certified test blocks. Each laboratory measured the hardness of each block 25 times.
The Leeb hardness test is of the dynamic or rebound type, which primarily depends both on the plastic and on the elastic properties of the material being tested. Verification of Apparatus 7. Originally approved in Each of the standard probes z956 its own characteristic direction dependency, which is determined by: In order to reproduce the standard direction dependency.
After placing the impact device on the test surface, trigger the impact body by exerting a light pressure on the release button. The charging tube is allowed to slowly return to the starting position. The complete reproduction law is obtained by interpolation between these curve points so that the corresponding amplitude value u t1 can be allocated to each voltage value u t0 enabling the velocity ratio except at the zero positions themselves to be calculated.
The results are, however, not completely independent on the impact angle. All such conversions are, at best, approximations and therefore conversions should be avoided except for special LE -5 -9 -4 -9 -4 -9 -4 -8 -4 -8 -4 -8 -3 -7 -3 -7 -3 -6 -3 -6 -3 -5 -9 -2 -5 -8 TABLE 1 Correction Values for Other Impact Directions: Consequently, there is no basis for defining the bias of this test method.
ASTM A – Free Download PDF Ebook
It is of advantage to arrange the impact body magnets and the coil so that the impact signal as well as the rebound signal uses at least two zero transitions in this case 3 of the induced voltage as support points for the evaluation of the curve. We need your help! No point shall be impacted more than once. Failure to provide adequate support and coupling will produce test results lower than the true hardness value.
Same materials to be tested like standard D unit but at extended hardness range. All such conversions are.