Microscope improves Brinell hardness reading

An Indentec Hardness Testing Machines product story

Edited by the Manufacturingtalk editorial team Feb 10, 2003

A new approach to measuring has improved the accuracy of reading Brinell hardness impressions for a leading heat treatment specialist.

A new approach to measuring has improved the accuracy of reading hardness impressions for a leading heat treatment specialist.

By adopting the latest handheld measuring microscope with built in LED (light emitting diode) illumination, Heat Treatment 2000 has maximised the clarity of Brinell hardness impressions in specimens, enabling inspectors to achieve more consistent measurements easily and quickly.

In common with many other firms, the West Bromwich Company previously used an external lighting source.

Supplied by Indentec, the new portable microscope is predominantly employed in the quality control of the 120 tonnes of aluminium and 250 tonnes of steel components processed each week, many of them in Europe's largest heat treatment furnace, rated for 2.7 tonnes/hour.

In service twenty four hours a day seven days a week, the Indentec instrument checks the hardnesses (generally from HB90 to HB120) of a wide variety of processed components, the majority for the automotive industries.

They include engine blocks, manifolds, sumps, suspension parts, wheels and bracketry in different configurations.

The impression is first made at the preselected point by a Brinell testing machine.

The microscope is then located over the indentation, which is illuminated by the LEDs and magnified 20X to allow the hardness to be determined to official standards through a measuring graticule with a resolution of 0.05mm.

Positioned internally to ensure a precise definition of the impression's edges, the four battery powered LEDs save any need to manoeuvre the lighting to 'pick' a good view for measurement, a practice that introduces variability into the process.

The Indentec scope also provides all the necessary illumination itself and is completely enclosed.

External light cannot reach the impression to distort the image measured.

Provided with a snap on base so that it can be stood upright when required, it is designed to measure impressions upto the 10mm Brinell ball and to check heat treated case depths on footprints down to 16mm long.