Dilatometric tests for the construction of CCT and TTT diagrams

Service description

Realization of dilatometric tests for the construction of continuous cooling transformation diagrams (CCT) and isothermal transformation diagrams (TTT). CCT- A metallic sample is heated to a defined temperature, hold it for a period of time, and then continuously cooled down to room temperature. TTT- A metallic sample is heated to a defined temperature, hold it for a period of time, cooled down to a defined isothermal temperature, hold it for a period of time, and then cooled down to room temperature. The phase transformation occurring in the continuous cooling process or in the isothermal plateau is registered by the measured change of length of the sample. For this type of measurements the dilatometry module of the Bahr 805D/A is used. Variant ciclo térmico básico 2 (basic thermal treatment 2, <= 1h) Will be applied to thermal treatments with a total duration <= 1h. Variant tiempo extra (extra time) (0-60 min, T <= 800ºC) Long isothermal holdings will be only applied at T <= 800ºC As many as necessary ¿tiempo extra¿ variants will be added to the basic thermal treatment 2 (ciclo térmico básico 2 ) to account for the extra time as compared to the basic thermal treatment (<= 1h). Example : In the case of a thermal/thermomechanical heat treatment with : Total duration = 90 min Extra time = 30 min Nº of ¿tiempo extra¿ variants to add to the ¿ciclo térmico básico 2¿ variant = 1 Total duration = 165 min Extra time = 105 min Nº of ¿tiempo extra¿ variants to add to the ¿ciclo térmico básico 2¿ variant = 2 The general conditions for this service are : Temperature: Induction heating. Thermocouples type K or S Tmin= room Tmax = 1150ºC (180-300s) Precission 0.05ºC Atmosphere Vacumm of 5*10-5 mbar Protected atmosphere of He Heating and cooling rates Heating and cooling rates 0.1-150ºC/s Sample dimensions Solid Ø = 4/3 mm y h = 10/12 mm For other geometries, please check with us.