BS ISO 7619-2:2010 Rubber, vulcanized or thermoplastic. Determination of indentation hardness. IRHD pocket meter method
This part of BS ISO 7619 specifies a method for determining the indentation hardness of vulcanized or thermoplastic rubber by means of a pocket hardness meter calibrated in IRHD. The use of such meters is primarily intended for control, not specification, purposes (for specification, see BS ISO 48). It is possible to increase precision by fixing the pocket hardness meter on a support.
The hardness of rubber, as measured by an IRHD pocket meter or a Shore durometer, is determined from the complex response of the rubber to an applied indentation. An IRHD pocket meter is a portable hand-held durometer calibrated to measure on the IRHD scale.
The measurement will depend upon:
a) the elastic modulus of the rubber;
b) the viscoelastic properties of the rubber;
c) the thickness of the test piece;
d) the geometry of the indentor;
e) the pressure exerted;
f) the rate of increase of pressure;
g) the interval after which the hardness is recorded.
Because of these factors, it is inadvisable to relate results obtained using an IRHD pocket meter directly to
Shore durometer hardness values, although correlations have been established for some individual rubbers and compounds.
Contents of BS ISO 7619 Part 2 include:
- Introduction
- Scope
- Normative references
- Principle
- Apparatus
- IRHD pocket hardness meter
- Test pieces Thickness
- Surface
- Conditioning and test temperature Procedure
- Test time
- Number of measurements
- Calibration and checking
- Calibration
- Checking using standard rubber blocks
- Test report
- Bibliography
