| 摘要 |
PURPOSE:To manufacture the titled steel free from crack and having good quality, by surrounding steel steel ingot having a specified compsn. contg. B, Crand Ni with iron tube tightly and adhering them pressedly, then hot rolling said body under a suitable condition. CONSTITUTION:15-21% Cr, 7.0-16% Ni system austenitic stainless steel ingot contg. 0.5-3.0wt% B, as it is or shaped to rectangular state, is surrounded tightly with iron tube made of soft iron, etc. at least four main surfaces excluding both end surfaces in longitudinal direction, and said body is bloom rolled or forged to adhere them pressedly. Next, steel ingot is heated to 950-1,250 deg.C, and hot rolled by at least one time, by 10-70% draft per one pass. Then hot rolled material is, if necessary, soln. heat treated, cold rolled, leveller straightened, etc., next, iron layer at outermost layer of circumferential surface is removed, to obtain the titled steel having good quality and free from crack and flaw at rim part in longitudinal direction of rolled material. |
