Heat treating is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is the heat treatment of metals. Heat treatment involves the use of heating (or chilling), normally to extreme temperatures, to achieve a specific result such as hardening or softening of a material.
Heat treatment techniques include annealing, case hardening, tempering, normalising and quenching. While the term heat treatment applies only to processes where the heating and cooling are done intentionally, these processes often occur incidentally during other manufacturing processes such as hot forming or welding.
In many cases the material or component looks similar before and after the process, which is where hardness testing comes in. Non-destructive laboratory testing of the component, or a sample of the material will give a value of the hardness which, if the equipment is calibrated, will be traceable to international standards. in practical terms, this means that if a customer orders certain components to be made of an alloy which should then be heat treated to give a specific hardness value, this can be proven and guaranteed.
Standards make the world work together, but only because there are dedicated teams of people meticulously ensuring when an instrument returns a measurement, that it is accurate and traceable. UK Calibrations calibrate, service and supply a wide range of hardness testing machines and provide calibration via UKAS to international standards.