Description
In the field of high-strength bolts (115000PSI), boron-type steels such as 10B21 have replaced grades like C1038. This first step has allowed reduction of the manufacturing sequence by eliminating the need for a soft annealing before cold forming. The final properties of the finished product are still obtained by a conventional quenching and tempering treatment. In order to also suppress this final heat treatment, and thereby simplify considerably the processing steps, Unimetal has worked towards the development of Dual-Phase steels.
