It is important to forecast decreasing heat levels in order to stabilize the quality of pig iron in a blast furnace. Kobe No. 3 B.F. is installed with 28 FM sensors- T (Doubly Sheathed Sensor with Multi Fine Thermocouples) which are located on the 4 locations at 7 levels from shaft to bosh of the furnace wall. These sensors can measure the temperatures in blast furnace with high accuracy. The temperatures measured by FM sensor- T are analyzed statistically in correlation with the pig iron temperature. Based on the analysis, a forecasting system far decreasing heat levels has been developed and applied to Kobe No. 3 B.F.
Through an on-line test of this system, the successful forecasting rate for decreasing heat levels was raised to 86%, and the alarm failure rate was 2%. The present system can be used as a guidance system for furnace operators.

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A mathematical model, capable of describing the macroscopic movement of an assembly of particles in a hopper, was developed based on the constitutive equations described by Voigt-Kelvin rheological model with a slider and on the equations o f motion for translation and rotation of each particle. The validity o f the present model was confirmed by comparing the results, such as the order of particles discharged from the hopper, arrangement of particles after charging in the hopper and stress distribution at the wall, obtained from calculations with the corresponding ones obtained by experiments as well as Janssen's equation.
The present model was successfully applied to the macroscopic flow of the assembly of granular materials consisting of different particle size under gravitational force in a hopper.
The installation of a repulsion box in the upper part of the hopper was also simulated and resulted in the decrease in the variation of particle size during discharge through the suppression of small particle segregation during charge, while it had insignificant effect on the deposit profile and the order of discharge.
The present model was, found to precisely describe frictional wall effect in solid flow and abnormal flow behavior, such as bridge formation, in comparison with the conventional continuous potential flow model.

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The formation process of burden distribution at blast furnace top was dynamically and quantitatively investigated by the use of a mathematical model, based on the equations of motion on distinct particles and the constitutive equation described by a Voigt-Kelvin rheological model with a slider. In order to increase the estimation accuracy of the mathematical model, the dashpot factor, which represents the kinetic energy dissipation of particles in the formation process of burden distribution, was experimentally determined.
The following findings were obtained through the application of the mathematical model.
The slope angle has significant influence on the burden deposit behavior throughout the charging. An increase of the amount of charge relates to an increase in charging rate, which results in a decrease of the deposit angle. The size segregation phenomenon on the slope can be quantitatively evaluated by the mathematical model. The change of the charging conditions of small particles onto the slope results in a change of the small particle distribution on the slope as well as a change of the deposit profile. A decrease of charging rate caused by an increase of charging time reduces the thickness of the flowing layer o f particles, resulting in the enhancement of percolation of small particles on the slope.

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A method for determining steady state temperature distribution in a blast furnace hearth lining is given. The isotherms can be determined by soloing so called inverse heat conduction problem, taking into account data obtained by measurements of temperature at selected points within the lining. An example is given.

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The theoretical equations which govern the one-dimensional flows of a gas particle mixture in a nozzle have been extended to the case where a continuous distribution of particle size is present. Using them a few numerical experiments have been performed for mist flows composed of air and water-particles, which are commonly applied to the secondary cooling zone in the continuous casting. The case has been treated where the radius of water-particle ranges between 1 and 50μm. Again, the nozzle with a parallel region in which the sectinal area is constant has been introduced to the numerical calculation. The results so obtained have been discussed from a numerical point of view. Furthermore, it has been pointed out that the flow properties strongly depend upon the particle-to-gas mass flow rate ratio, the reservoir pressure and the nozzle geometry.

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A series of electromagnetic stirring experiment was carried out in order to specify the most effective factor on generation of equiaxed zone. It has been shown that the volume of equiaxed zone has a good correlation with the wall shear stress calculated on the basis of the kW model of turbulence. The correlation is consistent both with the remelting theory of dendrite arms and the mechanical fracture theory of dendrite arms.

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The relation between phosphate capacity and different scales of optical basicity is examined and discussed.
The coexistence of monomer and dimer phosphate ions is considered and the amount of phosphorus as monomer phosphate ions is related to the slag phosphorus content. Excellent relationship is found between phosphorus capacity, temperature and theoretical optical basicity.
Optical basicities of TiO₂ and VO_y are derived and a linear relationship is found between the vanadate capacity,
C_VO^3-4=(%VO^3-₄)/[%V][%O]^5/2, and the optical basicity of basic steelmaking type slaps.

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The Fe-Zn and Ni-Zn alloy electroplated coatings were analyzed by the X-ray fluorescence spectrometric method. The critical thickness for an L series line is less than for a K series. The thickness of the common coating is greater than the critical thickness for the Lα line and smaller than that for the Kαline. The composition of the coating was determined only from the ZnLαline intensity. The coating weight was determined from the K series line intensity and the composition which was obtained from the ZnLα line intensity.

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Isothermal forging of Waspaloy disk was successfully carried out in air by using a new die material, “Nimowal”. The forging was done at 1070-1000°C at a strain rate of 10^-3s^-1 and the solution treatment at 1010-1038°C. Any damage or significant oxidation of the die was not observed. This shows that Nimowal can be practically used as a die material for isothermal forging in air. The weight of the forging stock was reduced and the microstructure of the disks was homogeneous as a whole. The microstructures and the mechanical properties of isothermally forged Waspaloy showed the characteristics compared with the conventionally forged Waspaloy;
(1) grain size depended primarily on forging temperature but was not affected by solution treatment temperature,
(2) yield strength increased as solution treatment temperature was raised, and
(3) creep rupture strength was high.
These characteristics were related to the dislocation structure and the volume fraction of coarse γ' particles in the microstructure of isothermally forged Waspaloy. The strengthening mechanism of isothermally forged Waspaloy was studied. The contributions of grain size effect according to the Hall-fetch relationship, the Orowan mechanism of bypassing of coarse γ' particles, the antiphase boundary strengthening due to cutting of fine γ' precipitates and the frictional force of matrix γ phase were analyzed.

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Mechanical and magnetic properties of Cr-Ni austenitic stainless steels have been investigated at cryogenic temperatures. Mechanical properties of weld metal have also been examined. Addition of N substantially increases the yield stress (σ_0.2) of steels with slight decrease in toughness. Mn increases σ_0.2 as well as toughness. Ni also increases toughness. A small addition of Nb increases σ_0.2 without deteriorating toughness. Mo also increases σ_0.2 without influencing toughness. σ_0.2 of weld metal is equivalent to that of base metal, while toughness of weld metal is lower than that of base metal. Mn raises Néel temperature and decreases permeability at 4K. The γ stability against martensitic transformation at cryogenic temperature can be quantified by a modified Ni equivalent. N, Mn and Ni increase Ni equivalent, which in turn increases the γ stability and maintains nonmagnetism at cryogenic temperatures. From these results, it is suggested that N, Mn, Ni and a small addition of Nb are very useful alloying elements to obtain Cr-Ni austenitic stainless steel having high strength, high toughness and nonmagnetism at cryogenic temperatures.

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The microstructure and tensile behaviour at room temperature of bronze-processed multi filamentary Nb₃Sn superconducting composite wire with titanium addition in bronze matrix were investigated after isothermal annealing treatment at 973 and 1073K up to 1720ks. The strength of Nb₃Sn compound was evaluated from the tensile behaviour of the wire, volume fraction of each component and stresses carried by ductile components (bronze, niobium and copper) at fracture of Nb₃Sn. It was found that the strength of Nb₃Sn compound decreased with increasing annealing temperature and time due to an increase in grain size and it was proportional to the inverse root of grain size in both cases of titanium addition and non-addition, which could be expressed by the Hall-Fetch type equation empirically. The strength was reduced by titanium addition.

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