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Ba(Ce,Zr,Pt)O3-perovskite is a new intelligent catalyst that shows self-regeneration of the precious metal. We previously reported that a Pd-perovskite catalyst, La(Fe,Pd)O3, regenerates itself through solid solution and segregation of Pd into and out of the perovskite crystal. We investigated the improvement of the oxygen-storage capacity (OSC) of an intelligent catalyst by means of suppressing the grain growth of the precious metal. The new intelligent catalyst is a composite comprising Ba(Ce,Zr,Pt)O3 perovskite formed on a CeZr oxide. We examined the self-regenerative function of the new material and tested its OSC and catalytic activity after engine aging at high temperature. The new intelligent catalyst was shown to have excellent durability of OSC and excellent catalytic activity.

With emission regulations getting tighter and tighter, catalysts will need to be active at ever lower temperatures in order to meet future standards. To meet this need, automotive catalysts are being installed closer to the engine so as to be active immediately after start-up. In this location, catalysts must have high temperature durability. In this paper, we examined a heat-resistant support material, “hexa-aluminate”, for possible use in future automotive catalysts. Catalytic activity of hexa-aluminate was more better than La added γ - alumina after redox treatment in model gas and after engine aging. Since hexa-aluminate had the excellent thermal durability, and Pd, which are supported on it, maintains finer particles than those on La added γ-alumina. We suggest that hexa-aluminate is a effective support material for automotive catalysts. More specifically, hexa-aluminate is expected to be a key technology for meeting the stringent emission standards of the future.

We have reported the innovation of “An Intelligent Catalyst” which has the function for self-regeneration of Pd realized through the solid solution and segregation of Pd in a perovskite crystal [1, 2, 3, 4 and 5]. We have looked for a design configuration for LaFePdO3 perovskite in the washcoat by comparing single and double layer washcaots as well as different loading locations for precious metals in order to maximize the Intelligent Catalyst's function in the practical conditions. The catalysts were attached to an engine exhaust system and subjected to an accelerated aging. The bed temperature of the catalysts reached to 1050 °C. The performance of the catalysts was evaluated on the engine dynamometer. Catalytic activity and long durability were improved by development of the washcoat configuration. The optimum design of the washcoat was double-layer with a tri-metal (Pt, Rh and Pd) system. The perovskite was located in the lower layer.

The influences of the transmittable torque capacity were evaluated using commercial CVT unit. We found that the contact surface between the belt and pulley lie in boundary lubrication. The maximum torque capacity difference among all tested fluids reached up to 40%. In order to analyze the friction characteristics of contact parts of CVT, a block on disk type friction test was created. As a result, the torque capacity in actual CVT correlated with the friction coefficient of the friction test. In addition, the effects of oil additives on the torque capacity were investigated. The combination of detergent (overbased calcium sulfonate) and phosphorus additive was the most effective for increasing friction coefficient. The formation of calcium carbonate, iron phosphate, and calcium phosphate on the friction surface possibly has a great impact on the increment torque capacity.

We have developed a Pd-intelligent catalyst with a self-regenerative function that is realized by the passage of Pd through consecutive solid solution and segregation states in and out of a perovskite crystal, and commercialized it for the first time in the world [1, 2, 3, 4, 5, 6, 7, 8 and 9]. In this study, we investigated the self-regenerative function of Rh as an alternative for Pd, in two types of Rh-perovskite (LaFeRhO3 and CaTiRhO3), and found that a CaTiRhO3 perovskite has an excellent capacity for the self-regenerative function of Rh. In a LaFeRhO3 perovskite with a composition similar to the Pd-perovskite (LaFePdO3), Rh was fixed so stably in the perovskite structure that it hardly segregated from the perovskite even in high temperature reduction atmospheres. However, in the CaTiRhO3 perovskite, with its A2+B4+O3 formula, the amount of Rh that actually segregated increased greatly in reduction atmospheres.

The use of Automatic Transmission Fluids (ATFs) with lower viscosity and excellent anti-shudder durability for wet clutch system will be effective for improving fuel saving performance in automatic transmissions. In this study, two ATF formulation techniques were examined. The first trial formulation is to improve fatigue life in gear components even if a lower viscosity ATF is used. The second one is to improve anti-shudder durability for wet lock-up clutch system in AT units. As to fatigue life performance, the relation between molecular weight of Viscosity Index Improver (VII) and film formation property in EHL contact regions were experimentally investigated. ATFs containing VIIs with lower molecular weight tend to increasing EHL film thickness, resulting in a longer gear pitting fatigue life. Calcium detergents and ashless friction modifiers in ATFs were found to give a great impact on the anti-shudder performance.

The aim of this study is to investigate how lubricants used for transaxles in hybrid electric vehicles (HEVs) and electric vehicles (EVs) give an impact on the cooling performance for electric motors. As a result, reducing lubricant viscosity improve heat transfer in both natural and forced convection conditions. Quantitative analysis could reveal that kinetic viscosity and heat conductivity of fluids are highly influential on the cooling performance. In addition, we investigated the effect of lubricant additive on fatigue life in bearing components by using a thrust needle roller bearing tester. Extreme pressure agent could control a morphology of the bearing raceway surface, playing a role in extending a fatigue life of the bearing.

The purpose of this study is to investigate how the kinematic viscosity of lubricating oil used in hybrid electric vehicle (HEV) and electric vehicles (EV) transaxles affects thermal conductivity and gear seizure resistance. This study investigated the relationship between viscosity, thermal conductivity and gear seizure resistance in detail and found that thermal conductivity tends to decrease with decreasing viscosity. It was also found that the thermal conductivity decreases significantly after a certain viscosity. The relationship between viscosity and gear seizure resistance was also investigated and it was found that too low a viscosity causes a significant deterioration in gear seizure resistance.