Study on Improving Hardness of TA1 Plate
Wang Huailiu (Titanium Branch, Sichuan Changcheng Special Steel Co., Ltd., Pangang Group, Jiangyou, Sichuan 621701)
To solve the problem of nonconfirming hardness(HRB) of TA1 plate, the factors affecting its hardness, such as inclusion content and its uniformity, rolling deformation and annealing temperature were studied in this paper. The results showed that the hardness of TA1 plate maily depended on the content of impurity elements, such as O, N, C and so on. By increasing the reduction ratio during rolling could increase the hardness of the plate, while increased annealing temperature decreased the hardness. So the conclusions were drawn: in oder to ensure the HRB not greater than 80, the requirements of O≤0.10%、N≤0.02%、C≤0.03% must be fulfilled while annealing temperature controlled at 750 ℃, in which case the hardness was in the specified range even if the reduction ratio reached 40%.