CALIBRATION OF INSTRUMENTS FOR HARDNESS TESTING BY USE OF A STANDARD

摘要

As a standard for the calibration of force and depth scales of hardness testing instruments a system of silicon springs is described. The standard shows a linear force-deflection characteristic F velence k (centre dot) f up to a stop point (typical: F_(st) velence 420 mN; f_(st) velence 22 (mu)m). For the calibration of stiffness and stop point of the standard the characteristic should be measured using a spherical indenter. In view of the practical application for the assessment of instruments also Vickers indenters can be used. In this case indentations are produced. The resulting wear can be minimized by reducing the maximum force and using only the measured stiffness k for a quick assessment.