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The 1200V class silicon carbide Schottky barrier diodes were designed and fabricated. The drift layer resistance was reduced in order to realize low forward voltage drops. Since the low drift layer resistance led to the low breakdown voltage, the avalanche withstanding capability should be enhanced not to cause the destructive breakdown. By means of the optimized device design, we succeeded to realize the low forward voltage drop while maintaining the high avalanche withstanding capability. The forward voltage drops at 200A/cm° were 1.35V at 25°C and 1.63V at 175°C, respectively. The avalanche withstanding capability was more than 3500mJ/cm₂ at 25°C. By substituting SiC-SBDs for Sipin diodes, the estimated total power loss of the module comprised by Si-IGBTs and the diodes was reduced by 35%. We could also confirm that no failures happened after long term reliability tests.

A new non-black (colorless) heavy load grease, having superior anti-seizure property and multi-purpose performance for construction machines, has been developed. The main components of the non-black heavy load grease are apertinent viscosity base oil, lithium complex soap and a unique non-black solid lubricant (phosphate glass). The weld load of the new non-black heavy load grease is 4900 N by the four ball EP tester. This value is almost the same as that of 60% molybdenum disulfide paste. The several type grease samples, mixed with 1 % clay dust, were evaluated by the four ball EP tester. The multi-purpose EP lithium grease lost the antiwear property and the MoS2 grease maintained antiwear property. The new non-black heavy load grease shows the best antiwear property against the clay dust. Furthermore, a number of laboratory tests have been conducted to prove the multi-purpose performance for construction machines.

An automotive powertrain total control system using estimated output shaft torque has been investigated in order to enhance drivability and improve fuel economy. The system provides efficient control for both the engine and transmission which leads to an enhancement in drivability by reducing shocks during gear shifts. This paper describes a new smooth gear shift control method using the total control system. By use of the estimated output shaft torque, it is possible to detect accurately the fluctuation condition and the start time of the inertia phase, which are important factors affecting shock occurrence. Torque feedback, got from estimated torque, was applied to the control of engine output shaft torque during shifts. The optimum hydraulic pressure, also got from estimated torque, was applied to the clutch of the transmission during shifts.

The Effects of microstructures on stretch flangeability and stretchability in hot rolled high strength steel was investigated. Stretch flangeability of multi-phase steels was inferior to that of single phase steels at a given tensile strength, although stretchability of the former was superior to that of the latter. In multi-phase steel, the main factor affecting stretch flangeability is the hardness ratio of ferrite to hard phase, on the other hand, that which most affects stretchability is the volume fraction of ferrite. According to these results, several types of high strength hot rolled steel sheets with excellent formability were developed.

The vehicle interior cover material requires good cloth hand and sewability with no wrinkle-and-slack to produce a superior quality. Usually, the evaluation for the cloth hand of cover materials depended on subjective judgement, and for the sewability has been relying on the experience of an expert. Therefore, an objective evaluation has not been performed. As the result, there were some cases where this matter has become a subject of discussion at planning and producing. In this research, the correlation to the usual measuring method, evaluation, and sewability was performed by measuring the very subtle values of cloth mechanical and surface properties. The results in outline are as follows; The test precision has been improved by applying the new evaluation method. The cloth hand for each kind of cover materials has been quantified by applying the mechanical properties.

To produce high quality appearance interior parts, precise pattern forming or gloss reduction of three-dimensional door trim cover materials are utilized. In the preparation of formed trim cover using polyvinyl chloride (PVC), prior pattern forming on original cover material or post-pattern forming with vacuum forming dies are employed. In the latter case, the die is usually made of epoxy resin. Although vacuum holes are prepared on the resin die as necessary, the lack of uniformity in air permeability causes inferior pattern transferability. In this development, special porous ceramic die is used as die material so that trim cover material can be evenly sucked through the fine pores on its surface. As a result, a door trim forming die of superior pattern transferability has realized.

Variation of the total hemispherical emittance of spacecraft thermal control films resulting from irradiation is discussed. An electron energy of 30 KeV and a UV intensity of 3 sun equivalents are used. The emittance is measured in situ by the calorimetric method. The emittance of silver-Teflon film increases slightly with increasing the electron fluence. Its increment is less than 0.02 at a fluence of 1 × 1015 e/cm2, and very small for further irradiation. Addition of UV rays does not alter this situation. The emittance of aluminized Kapton film is not changed appreciably by irradiation.

For the computation of the equilibrium combustion temperature and pressure of hydrocarbon fuel in air, an original set of eighteen equations is enlarged by the energy and mass balance, and the procedure is applied to the cases of constant volume and of constant pressure combustion. Examples of engine combustion, including the effects of air-fuel ratio and the effect of water injection or exhaust gas recirculation, are treated; the results of computation are presented in graphs. The procedure of transformation and coding of the equation system for the solution on an electronic computer is described.