Experimental Research On Ship Plate By Reducing Resources With Flexible Rolling Technology

Flexible rolling technology which can not only save energy,simplify production operation, but also reduce production cost greatly is originated from TMCP (Thermo-Mechanical Control Process). With the development of this technology in research and industrial application, it has been attracted wide attention in steel industry at home and abroad. The experiments were carried out based on C-Mn steel without adding any microalloy element such as Ni,V,Ti, combined with the project "New Manufacturing Technology on Ship Plate by Reducing Resources with Flexible Rolling" with Sanming Steel in this paper.In the lab we study on the effects of controlled rolling and cooling process on microstructure and mechanical properties with different carbon equivalent and in the end we determined the flexible rolling process system.The contents and conclusion was summarized as follows:(1)Using three different rolling processes in the lab, the experimental results of the test steel are showed that:in the same process, the effect of carbon equivalent is the main factors for the mechanical properties. With the increasing of carbon equivalent the strength performance of the tested steel get better, but the plasticity and toughness get worse. Considering various factors, the reasonable chemical composition and carbon equivalent are determined which provide the basis for industrialization of economizing ship plate;(2) With the TMCP processes of the industry billet in the lab, the deformation, temperature and cooling system were studied on respectively. It concluded that cooling in the air condition after controlled rolling, the grain size is more coarser and the plate showed worse comprehensive properties than that of controlled cooling. With the increasing of the intermediate slab thickness the tensile and the impact properties get better and the tested steel show the same performance with the decreasing of finish temperament. In the end we determined the rolling process of A32, D32 high strength ship plate. The starting temperature of finishing rolling was at 850±10℃,the thickness of intermediate slab was two to three times than product plate,laminar cooling system was employed at the speed of 10～15℃/s after rolling and the final cooling temperature should be at 670±10℃;(3) Refering to the results of the lab experiments and date of industrial pilot, we determine the chemical constituents and rolling schedule which are suitable for the A36, D36 high strength ship plate.The flexible rolling process for B,D common ship plate which has already being produced in the Sanming Steel.The mechanical properties of the B,D common ship plate meet the requirements of relevant national standards and the product has been passed the certification of the China Classification Society。...