The Innovation and Technology Commission (ITC), Hong Kong

As part of ITC the Standards and Calibration Laboratory (SCL) is a HOKLAS accredited ISO 17025 calibration laboratory that provides calibration services for electricity and magnetism, time and frequency, temperature and humidity, photometry and radiometry, acoustics and vibration, dimension and mass and related quantities including material hardness.The Laboratory can provide hardness measurement of components and indirect verification of hardness testing machines of the following scales: Vickers, Rockwell B and C and Superficial Rockwell and produce test blocks.
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SCL were looking to expand their Vickers hardness testing capability and were looking for a standardising Vickers machine for the production of test blocks and to replace an old Vickers pedestal tester. The force application accuracy requirements for standardising machines of ISO 6507-3 are stipulated to be +/-0.1% for Vickers and +/-0.5% for Micro Vickers, much more demanding than specified by ISO 6507-2 for an industrial Vickers tester of +/-1% and +/-1.5% respectively. Such requirements are challenging to meet and few hardness tester manufacturers have the capability.

A technical specification was drawn up after an investigation of the most appropriate testing machines. A number of world class hardness tester manufacturers were investigated for metrological standards, including force accuracy, ease of use and life cycle costs.

Technical proposals were requested from Hardness Tester manufacturers. Indentec, with their local sales partner Wallok Engineering Co. Ltd, offered the ZHV50-AS Vickers Hardness testing machine, together with installation by an Indentec UKAS accredited calibration engineer. The ZHV50-AS machine is a dead weight hardness tester capable of delivering force accuracy to meet ISO 6507-3. Indentec could also offer UKAS certified Calibration and Measurement Capabilities and traceability to the German National Physical Laboratory (PTB). In addition the automatic indentation measurement by Indentec's ZHμ.HD software provides rapid, reliable, repeatable and reproducible measurement, with none of the subjectivity associated with human manual measurement.

SCL have owned an Indentec ZHR8150TK Combined Rockwell hardness tester since 2009 and were impressed with the excellent reliability, and ease of use. The machine has delivered reliable hardness test results since installation, and is simple to calibrate.

The ZHV50-AS was installed in November 2016 by an Indentec service technician. A full training program for the end users was also conducted. The machine has been performing reliably since installation and end users are comfortable using the machine.

The automatic ZHμ.HD software, has user friendly interfaces and extremely fast and reliable automatic indentation focus and measurement. A full training package for the end users has ensured that they could take full advantage of the HD software functionality.

Indentec also installed new diamond and 1/16" ball indenters, calibrated the current ZHR8150TK to ISO and ASTM standards and issued a UKAS calibration certificate.