||Revision of E 10 Brinell Hardness Standard Now Requires the Use
of Tungsten-Carbide Balls
A revision to the ASTM E 10, Standard Test Method for Brinell Hardness of Metallic Materials,
that requires the use of the tungsten-carbide ball indenters for
all Brinell hardness testing, has been approved by Committee E28 on Mechanical Testing.
As a result, the tungsten-carbide ball will now be required for
all hardness ranges including the softer materials below 450 HBW
where the steel ball was previously allowed. This change is expected
to improve the performance of the test by eliminating the risk
of ball flattening that steel balls experience and increase the
useable life of the ball to the user. In addition, ASTM E 10 now
aligns with ISO 6506, Metallic Materials-Brinell Hardness Test,
with regard to indenter usage.
Brinell hardness test users should only use testblocks calibrated
with the carbide ball. The designation HBW should be used exclusively
to denote the tungsten-carbide ball in use. Between 300 HBW and
450 HBW, the user may find a small shift in values due to the
difference in the elastic properties of the steel and tungsten-carbide
balls, however it is considered to be negligible.
A task group of ASTM Subcommittee E28.06 on Indentation Hardness
Testing developed the revision. For further technical information
contact the task group chair, Robert A. Ellis, Quality Manager, David L. Ellis Co., Inc., Acton, Mass. (phone:
978/897-1795; fax 978/ 897-0844).
Committee E28 meets May 7-9 in Phoenix, Ariz. For membership or
meeting details, contact Staff Manager Daniel Shultz, ASTM (610/832-9716). //
Copyright 2001, ASTM