Brinell Hardness

Brinell hardness (HB) testing shall be performed in accordance with the latest revision of ASTM E10. Deviations to this procedure are permissible so long as the client requests an alternative method or procedure. Alternative methods or procedures shall be noted on the Lab worksheet.

Brinell testing is done with the calibrated Brinell machine that applies a predetermined indenting load to a ball in contact with the specimen. The ball is a 10 mm ball used to apply load of 3000, 1000, or 500 kgf depending on the material for 10 to 15 seconds.

Calibration of Brinell tester shall be done prior to any test run for the day. Each block for calibration will have NIST traceability. The full load shall be applied for a full 15 seconds during the calibration process.

The specimen submitted for testing should be flat and parallel. The thickness should be that no bulge or other marking showing the effect of the load appears on the side of the piece opposite the impression. The surface of specimen shall be filed, ground, machined or polished so that the edge of the impression shall be clearly enough defined to permit measurement of the diameter.

Place the test piece on the base of the Wilson Brinell tester.  Raise the sample to bring in contact with the 10mm ball, apply the specified load and hold for 10 to 15 seconds.  Release load, remove test piece and measure the impression with the B & L 20X scope to the nearest .5mm.  Use the Brinell hardness number table on ASTM E10 to find the proper Brinell value according to the load used.  When permissible report an average of 3 readings.  Report the Brinell hardness number, load used and ball size.