ASTM B724-00(2006)

The instrument may be used on a variety of geometries of aluminum alloy test pieces, providing the surface being tested has proper support for the instrument.

This test method is intended for quality assurance and production control purposes. This test method is not intended to be an independent material-acceptance test.

The thickness of the test piece shall be such that a mark or bulge is not produced on the reverse side of the test piece and the test piece does not deflect during the test.

Calibration of the instrument through the use of reference blocks is required for true comparative hardness values.

1.1 This test method covers indentation hardness testing of aluminum alloys using a Newage, portable, non-caliper-type, hardness instrument which provides readout values numerically equivalent to Rockwell B-scale as determined by Test Methods E 18.

This is a comparative Rockwell B test and does not provide an actual Rockwell B test value. HRBN, the values obtained from the Newage instrument, are numerically equivalent to Rockwell B values, but do not represent an actual Rockwell B test in accordance with Test Methods E 18.

1.2 This test method measures indentation hardness of heat-treatable aluminum alloys having a hardness from 30 to 100 HRBN, a thickness greater than 1.50 mm (0.060 in.), and pieces too large to be tested by a caliper type instrument.

This test method covers two instruments (one analog and one digital) which operate differently. Refer to the manufacturer's instruction for proper operation.

1.3 The flat surface size of the area being tested must be compatible with the instrument support area and the material must not deflect during the test.

1.4 The values stated in SI units are the standard. The values given in parentheses are for information only.