摘要 |
A boron alloying additive for continuous casting of boron steel having the desired hardenability without tundish nozzle blockage. The additive comprises 0.25-3.0% boron, 2.5-40% rare earth metals (RE), 6-60% titanium, and the balance iron. The additive may also contain silicon, calcium, manganese, and zirconium. In the additive the weight ratios of Ti to B and (Ti+RE) to B are 20:1-60:1 and 30:1-90:1, respectively. |