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9. Materials Testing Machines

Siegfried Gerber

The first DKD calibration laboratory for the calibration of materials testing machines was accredited on 10 February 1994. In the same year - on 28 June 1994 - the first meeting of a corresponding expert panel which had emerged from the Technical Committee "Force, Pressure, Mass" took place, back then under the name "Working group for Materials Testing Machines". The meeting was held at PTB and was attended by 23 participants.


This expert panel, now called Technical Committee for Materials Testing Machines has taken on the task of discussing topics regarding the calibration of materials testing machines. This includes the calibration of universal testing machines, hardness testing machines, pendulum impact testing machines and testing machines for building materials as well as the calibration of extensometers. Each year, more than 60 participants from seven European countries take part in the meeting of the Technical Committee "Materials Testing Machines".


The fact that a large number (between 70% and 80%) of laboratories accredited by the German Accreditation Body (DAkkS) regularly attend the meetings means that the Committee does provide a good overview of the calibration landscape in the field of materials testing machines. This enables efficient work and ensures homogeneous implementation of the standards and guidelines in the accredited laboratories. The meetings are also attended by observers from the accreditation body who provide information on the latest developments.


Furthermore, the meetings provide information from representatives of PTB and DIN regarding new standards and committee activities. Thus, the drafts can be discussed, and proposals can be submitted to the respective committees. Moreover, the Technical Committee organises interlaboratory comparisons, discusses current developments and topics, draws up complementary guides to standards or prepares DKD guidelines in its various working groups. The fact that the chairman of the Technical Committee on Materials Testing Machines also chairs the DIN Working Committee on Materials Testing Machines
(NA 062-08-11 AA) and acts as deputy chairman of the DIN Working Committee on Impact Toughness Testing for Metals (NA 062-01-44 AA) contributes to an effective functioning.


The annual meeting is usually held after that of the Technical Committee "Force, Acceleration and Acoustics" and prior to the meeting of the VMPA Working Group "Testing Machines and Equipment"; thus, synergies can be used.


The Technical Committee "Materials Testing Machines" is currently working on a guideline (DKD-R 9-3) regarding supplementary procedures for the calibration/testing of hardness testing machines.


The Technical Committee has already published the following documents:


·         DKD-R 9-1: Calibration and verification of the torque measuring device of torsion testing machines

·         DKD-R 9-2: Supplementary information regarding the calibration/verification of tensile/compression testing machines