Ovako says it now has 37 different material grades of low-alloy boron steel in its melt programme. The company claims these, when heat treated, can achieve properties comparable with those of higher alloy steels.
To produce this only small additions of boron are required which, in combination with carbon and other alloying elements, increase the hardenability of the steel. Cold-formability of boron steel grades in the ‘as rolled’ condition is claimed to be extremely good, so no annealing is required. This is advantageous when the steel is to be used in cold forming or blanking processes.
The company claims its typical boron steel grade bar, between 25-40mm diameter after hardening and tempering at 500°C, produces a yield strength of 750Rs N/mm², tensile strength of 900-1050Rm N/mm² and a hardness of 275-32HB.