A hydrothermal-assisted cold sintering process is developed for preparing antiferroelectric NaNbO 3 ceramic. The novel process includes hydrothermal synthesizing NaNbO 3 particles, cold sintering, and annealing. The physical and electrical properties of the cold sintered ceramics were studied comprehensively and compared with ceramics prepared by conventional sintering techniques. At optimum conditions, dense ceramic can be prepared by the cold sintering process with very low heat treatment temperature, and the properties are comparable with that prepared by conventional sintering.

Low-silica pellet is beneficial for blast furnace to reduce the amount of slag and fuel rate. However, the reduction swelling of low-silica pellet is serious. The effects of TiO 2 and MgO on such metallurgical properties as reduction swelling, reducibility and smelting performance of pellets have been studied and production of magnesium-titanium-bearing pellet with low silica is proposed in this paper. The MgO in sinter can be transferred to pellet and TiO 2 is provided by the pellet for blast furnace to protect hearth erosion. The magnesium-titaniumbearing pellet with low silica, in which the content of MgO is 1.7%, SiO 2 is 2.8% and TiO 2 is 1.2%, has been produced by the raw materials from Shougang Jingtang United Iron & Steel Co., Ltd. The pellets were used on 5500 m 3 blast furnace with a ratio of more than 28% stably and good technical and economical indexes were obtained. The average particle size of sinter was improved when the MgO content of pellet is increased without adding magnesium additives to sinter.

Due to the problems of very serious wear, serious scale and poor ability to controlling strip shape of work roll, considering the advantages/disadvantages of HSS roll and the field practices, a 3D elastoplastic FEM model of rolls system with strip, which is used to analyze the ability of strip shape control of rolls system when HSS rolls work at any two stands of F1-F4, is modeled. The calculating results sho: The control ability of mill is relative greater when HSS rolls are used at F4, the advantages of HSS roll are not taken fully if HSS rolls work at F1 and F2. And HSS are available for either F2 or F3, furthermore, F3 is better for shape control. The analysis results are verified by the experiments. A strong theory base of application of HSS rolls in Hot Strip Mill is brought forward in this paper.

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