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Engine technologies using efficient combustion and down-sizing turbo have become important in order to reduce automotive CO2 emissions. However, the exhaust gas temperature also becomes lower by these technologies. As a result, the catalyst performance becomes lower. Therefore it is necessary to develop low temperature active catalysts to reduce emissions. This research was focused on Pd/CeO2, and it’s able to oxidize CO at low temperatures. In order to increase the catalyst activity, the addition of some elements to the CeO2 was studied. Zn addition was found to have an advantage to reduce the CO light off temperature by 60 °C. Then, we tried to clarify the cause of improvement. As a result, it made clear that the Zn addition promotes the active oxygen release from the CeO2 surface. However, repeated engine exhaust gas tests indicated a decline in purification performance.

Regulations that limit emissions of pollutants from gasoline-powered cars and trucks continue to tighten. More than 75% of emissions through an FTP-75 regulatory test are released in the first few seconds after cold-start. A factor that controls the time to catalytic light-off is the heat capacity of the catalytic converter substrate. Historically, substrates with thinner walls and lower heat capacity have been developed to improve cold-start performance. Another approach is to increase porosity of the substrate. A new material and process technology has been developed to significantly raise the porosity of thin wall substrates (2-3 mil) from 27-35% to 55% while maintaining strength. The heat capacity of the material is 30-38% lower than existing substrates. The reduction in substrate heat capacity enables faster thermal response and lower tailpipe emissions. The reliance on costly precious metals in the washcoat is demonstrated to be lessened.

With the increasing number of automobiles, the worldwide problem of air pollution is becoming more serious. The necessity of reducing tail-pipe emissions is as high as ever, and in countries all over the world the regulations are becoming stricter. The emissions at times such as after engine cold start, when the three-way catalyst (TWC) has not warmed up, accounts for the majority of the emissions of these pollutants from vehicles. This is caused by the characteristic of the TWC that if a specific temperature is not exceeded, TWC cannot purify the emissions. In other words, if the catalyst could be warmed up at an early stage after engine start, this would provide a major contribution to reducing the emissions. Therefore, this research is focused on the substrate weight and investigated carrying out major weight reduction by making the porosity of the substrate larger than that of conventional products.

This paper presents an improved CAE method for high-accuracy warpage analysis. The physical properties of the materials that affect warpage are examined, considering the mechanisms at work in each of the three steps of the injection molding process: injection, pressure holding, and cooling/ejection. When a theoretical mechanism is not fully understood and measurements are inaccurate, correction is made based on the measurement values of large, thin parts. This paper describes both the analysis and application from more than two years of study using the new CAE method.

Warm Shot Peening is a shot peening process within warm temperature range. However, the effect of warm shot peening to fatigue strength was not certain and no substantial study has been made. The requirements of coil spring with higher fatigue strength and sag resistance have been increasing to obtain the mass saving of vehicle. While several new spring materials have been developed in recent years, the essence of those developments were to make the strength(hardness) of spring higher, so-called high strengthened spring. As for high strengthened spring, the shot peening process becomes further essential to relieve the increased notch sensitivity due to higher strength. However, for the shot peening process to high strengthened spring, the shot with higher hardness is also required. This can decrease the life of both shot and shot peening equipments.

For the purpose of weight-saving of automobile, stabilizer (anti-roll bar) is now being designed by tube. This paper is mainly concerned with the basic consideration of designing hollow stabilizer. The mechanics of the stress distribution which occurs to hollow stabilizer, was obtained experimentally. It was found that the stress condition of hollow stabilizer was entirely different from that of solid stabilizer. The application of pipe factor makes it possible to predict the design stress of hollow stabilizer. The experimental results have good agreement with the calculated results obtained by Finite Element Method.