Solution Annealing
Products requiring treatment with a known history shall be placed in the furnace at an unrestricted temperature, however it may be required for certain materials (Duplex & Super Duplex which may contain some sigmatisation) to load the furnace at a temperature not exceeding 400°C and then using the program control system raise the temperature in 200°C per hour increments until the temperature reaches the austenatisation temperature. After the furnace has equalised the load shall be soaked to allow all detrimental phases to be dissolved prior to quenching, this is can be calculated utilising phase diagrams, TTT curves and the Schaeffler diagram to calculate the phase balance from the analysis, however for certain products experience is essential as this can be a balancing act between retaining product shape and dimensions whilst obtaining the desired structure free from Sigma, Chi & Laves phases
The products are removed from the furnace and rapidly quenched in agitated water. The time to transfer the fittings to the agitated water tank shall be a maximum of 45 seconds.
The products shall stand in free air for 2 hours before further workmanship takes place.
