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The anodic oxide films are formed to improve the corrosion resistance on aluminum alloy that used as the parts of engines and car bodies. Because these films are porous structure, it is necessary to seal the pores to further improve the corrosion resistance. The pores are sealed with hydrated alumina by treating the films in boiling water or solution that added sealing additives. These hydration sealing has a problem that energy consumption is large because of long sealing time and high temperature of solution. In this study, the authors have developed a new sealing treatment (Lithium sealing) using a lithium hydroxide solution to solve above problem. Lithium sealing mainly sealed the pores with lithium aluminate double salt (LiH(AlO2)2·5H2O). This salt was rapidly formed in strong alkaline solution at room temperature, so that the sealing time was reduced to about 1/10 compared with the conventional sealing.

Anodizing is applied to improve the durability and the corrosion resistance of aluminum alloy parts of engines and car bodies. Generally, anodic oxide film is formed using direct current anodizing (DCA). However, in the case of anodizing high silicon aluminum alloy cast parts, it is difficult to derive uniform film thickness distribution. Furthermore, it takes a long treatment time which causes low productivity. In this study, the authors have developed an anodizing method by using high-frequency switching anodizing (HSA) to solve these problems. The growth process of anodic oxide film is susceptible to the metallographic structure. Thus, the typical DCA application to the high silicon aluminum alloy produces a non-uniform film thickness, while HSA has the potential to form uniform film without being affected by metallographic structure. Moreover, the current density of HSA is higher than that of DCA which reduces treatment time to 1/5 as the film formation enhances.

The role of molybdenum and its substitute elements in carburized layer has been examined. Among substitute elements, chromium and manganese are effective to raise case hardenability. Chromium is also effective to raise surface carbon content. Boron suppresses over-carburizing. Silicon enhances structure anomalies. Based on these results, five kinds of molybdenum-saving case hardening steels have been designed. These steels showed good carburizing properties.

A computer aided experiment system utilizing optical fiber communication has been developed for automotive engine research and development at the Toyota Higashifuji Technical Center. The objectives of this system are to establish both low and high speed data acquisition and processing capability by introducing minicomputer based intelligent terminals and connecting them by optical fiber cable to a special processor controlling a group of the terminals. A host computer controls the special processors and the whole system works as a hierarchical and distributed function system. By introducing this system, high speed data sampling and online data processing become possible at every test bench.