Although conventional agglomerates, such as pellets and sinter, have superior properties for the blast furnace, they also have inferior properties. The purpose of the present investigation was to develop a new iron ore agglomeration process that differs from the conventional ones and thereby to improve the properties of the agglomerates. The main results obtained are as follows:
(1) Differing from conventional mini-pellet-bearing sinter, the agglomerates, composed of diffusional bonding structures, are constituted from aggregates of irregularly shaped pellets restricted to between 5 and 10mm in diameter.
(2) Fine ores such as pellet feeds can be used in large quantities as raw materials for this process, differing from the conventional sinter processes, because they are granulated completely.
(3) According to an estimation of methods for the addition of fine coke to the raw materials by the mathematical model, it became clear that the method for preferential addition of cokes to the surface of green balls was suitable because of effective coke combustion. This was verified by pot grate, furnace tests.
(4) The properties of the new experimentally produced agglomerates were found to be superior to those of sinter. The desirable properties were considered dependent mainly on micro- and macro-structures and process characteristics.

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For the utilization of petroleum coke-oil slurry as a substitute fuel for blast furnaces, the development of an injection technique of petroleum coke-oil slurry into a blast furnace was taken place. The petroleum cokes used in this study were delayed coke (DC) and fluid coke (FC).
Laboratory tests and a pilot plant test were carried out for a study of rheological properties of slurries. It became clear that DC slurry has much higher viscosity than heavy oil and FC slurry has higher settling velocity than DC. Based on these results, a slurry injection system was designed and a demonstration plant test was performed at Kobe No. 1 BF with 4 tuyeres injection for over 4 months. The sampling of gas and dust was performed to evaluate the combustibility of slurry in the raceway.
It was confirmed that it was possible to inject 50% slurry without additives as easily as heavy oil for a long period and the new injection system using a circulating loop provided a circumferentially uniform distribution of injected slurry. The combustibility of the substitute fuel decreased in the order of heavy oil, DC slurry and FC slurry. Moreover, the replacement ratio of slurry to coke was estimated to be about 1.0.
Consequently, it is concluded that petroleum coke-oil slurry can be used as a substitute fuel for blast furnaces.

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The rate of silicon oxidation between Fe-4.4% C-Si alloy and Li₂O-CaO-SiO₂-FeO slag has been investigated under the condition of mechanical stirring at 1300°C. The initial concentrations of FeO in the slag, (%FeO)₀, and of silicon in the metal, [%Si]₀, were 2.5-30 and 0.008-0.1, respectively. The rotating speed of stirrer was 50-400rpm. The activity of SiO₂, a_SiO2, in the slag has also been determined experimentally by measuring the concentration of silicon in carbon saturated iron equilibrated with SiO₂ in the Li₂O-CaO-SiO₂ slag at P_CO=1 atm and 1300°C.
Under the experimental conditions adopted, the apparent mass transfer coefficient in the metal phase, k'_Si, increases with increasing (%FeO)₀, while k'_Si does not change much with varying [%Si]₀. It is found that k'_Si increases approximately in proportion to the 1/3 power of the rotating speed of stirrer. However, the effect of mechanical stirring on the mass transfer of FeO in the slag is negligible except at low (%FeO). A mathematical model describing the simultaneous reactions of silicon, carbon and FeO is proposed. The reaction mechanism of the slag-metal reactions is explained with the aid of the mathematical model proposed.

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In Ni-base superalloy René80 ribbon produced by a twin-roll rapid solidification process, the secondary dendrite arm spacing (SDAS) becomes smaller at the center of the thickness direction and the interfaces are observed between the initial and final solidification areas. By simulation of the solidification process of ribbon by the finite difference method, it is pointed out that the process is composed of three stages in the light of heat transfer. The distribution of secondary dendrite arm spacing calculated is in good agreement with the one measured.

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Green compacts of hematite (54% porosity) were sintered in air at 1000°C for 30min and at 1300°C for 180min to produce porous (35% porosity) and dense (8% porosity) compacts, respectively. Hematite compacts were isothermally reduced with hydrogen at 500-1100°C using weight-loss technique as a function of time. The structural changes accompanying sintering and reduction processes were examined with mercury pressure porosimeter and optical and scanning electron microscopes. The reduction of porous and dense samples reveals the presence of reduction rate minimum at 650°C which was attributed to sintering and densification of the freshly reduced iron around the oxide grains. The retardation in the rate at 650°C was increased with the increase in the reduction extents and with decrease in the porosity of the compacts. The computed values of activation energy were correlated with the corresponding reduction mechanisms.

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Water model experiments have been conducted to determine the mixing time in hybrid process with five circular tuyere arrangements. Complete mixing time of water has been determined by tracer technique. It has been shown that bottom gas flow rate per tuyeres and tuyere arrangement do not have much effect on mixing time. On the other hand, the number of tuyeres has a pronounced effect. The mixing time in hybrid process with different tuyeres arrangement was found to be higher than L.D. model except in one case. It has been speculated that the metallurgical and operational improvement in hybrid process over L.D. is not dependent on the lower mixing time due to bottom gas injection alone.

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In a comparison market review, it has been found that, in Europe, three-piece cans are mostly produced as food cans with paper labels. Such cans are now almost exclusively made from tinplate with a welded side seam.
In this article, the possibilities of improving the economics in the production of the cans will be described taking into account technical limitations:
i) Lower tin coating weight limits required by the welding operation. Restrictions due to corrosion under today's lacquering conditions. Improving the tin coating uniformity to meet these requirements.
ii) Using minimum possible metal thicknesses with a view to providing stability of can body and end under sterilization, distribution and storage conditions. The necessary material improvements will be described.
iii) Manufacture of cans with low body wall thicknesses by flanging. Special conditions to be observed, if high-strength steel, such as DR material, is used. Current can specifications in Europe.
iv) Current can specifications in Europe.

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In Europe, two-piece cans from tinplate are mostly produced as DWI cans for carbonated beverages. Two-piece DRD cans of small height are produced from pre-lacquered ECCS for food can applications.
The limitations of the deep-drawing process will be described. The importance of the limiting drawing ratio for producing the cup and the influence of friction and lubrication on this ratio will be discussed.
The wall-ironing process and the influences of the material quality on this process will be explained, together with the final manufacture of the cans by necking and flanging.
Finally, the necessity of new developments for using even lower body wall thicknesses and the use of higher-strength steel materials will be discussed.

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The effect of hydrogen on the tensile properties of warm rolled high carbon steels was studied experimentally. Two kinds of steel, 1.27% C and 1.24% C-12% Mn, were isothermally rolled at 930K to yield fine spheroidized particles in matrix. Tensile tests were performed with specimens of cathodically precharged hydrogen. The occlusion of hydrogen in 1.2% C steel was greater than in 12% Mn steel, and much hydrogen was trapped in the rolled structure than in the forged one. The tensile strength decreased a little, but the loss of the reduction in area is greater than that of the tensile strength due to the precharged hydrogen. Decohesion of the interface between matrix and carbide particles in a hydrogen charged rolled steel was attributed to the change in ductility. A change from a micro-void coalescence to a quasi-cleavage pattern is affected by hydrogen.

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