The Tempcore process is a specially developed cooling process to give the reinforcing bar high quality performance. The bar is cooled with water under high pressure.
The outer layer of the bar is cooled to 300 °C from 1 000 °C. The heat in the core of the bar then reheats the outer layer and tempers the martensite.
The process, therefore, gives a core of pearlite and ferrite, a transition area, and an outer layer of martensite.