Microhardness Testing and Hardness Numbers

  • Anton F. Mohrnheim


In this paper, the Vickers and Knoop hardness test methods for the determination of microhardness are discussed and a simplified method for comparison of numerical hardness number values are presented. Microhardness testing enables the testing of thinner and harder materials than ever possible by macrohardness testing. Increased demands on the strength of miniature parts, and a growing interest in the initiation and growth of microcracks of materials, as well as required close quality control of protective surface coatings, have created a great need and interest for miniload hardness testing.


Microhardness Test Hardness Number Diagonal Length Indent Load Knoop Hardness 
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Copyright information

© Plenum Press, New York 1977

Authors and Affiliations

  • Anton F. Mohrnheim
    • 1
  1. 1.University of Rhode IslandKingstonUSA

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