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Several different steel sheets were tested for energy absorption, using hat square columns and dynamic crash testing. Results indicate that steel sheets containing large volume fraction of retained austenite have relatively high energy absorption. The relationship between retained austenite and energy absorption was analyzed. These special steel sheets have already been successfully used for production body parts, such a front-side-member, without difficulties arising in volume production.

General purpose engines are required to keep the engine speed constant, and are therefore equipped with governor mechanisms. However, the engines are applied to various applications, and the dynamic characteristics of the controlled engine changes according to different operating conditions. To enhance robustness, an adaptive control system that uses a self-tuning regulator has been constructed. Applying elliptical gears to the mechanism for driving the throttle valve, it was possible to realize both high resolution near the closed position and a reduction in operating time of the throttle valve.

Automotive parts produced by cold or hot forging steel bars are often heat treated after forging to reduce their grain size and obtain improvements in mechanical properties such as tensile, impact and fatigue properties. If heat treatments after forging can be eliminated, savings in energy and handling costs could be realised. Although rolling and cold drawing without additional heat treatments have been already used, hot forged components have not except a few applications because of low toughness properties when heat treating after forging is omitted. Tests in our laboratory have shown that the toughness and other mechanical properties of hot forged parts can be significantly improved without the use of post heat treatments. Results were as follows: 1. High strength and high toughness are obtained by decreasing carbon contents, increasing manganese, adding both of microalloying elements (V, Ti). 2.