Metallic materials. Knoop hardness test - Verification and calibration of testing machines included-in-kit Annex A (normative) Materials and

Annex A (normative) Materials and

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Metallic materials. Knoop hardness test - Verification and calibration of testing machines included-in-kit Annex A (normative) Materials and1 Scope This document specifies the method of verification and calibration of testing machines for determining Knoop hardness for metallic materials in accordance with ISO 45451. A direct method of verification and calibration is specified for the testing machine, indenter, and the diagonal length measuring system. An indirect verification method using reference blocks is specified for the overall checking of the machine. If a testing machine is also