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Ausforging, in which quenching is performed direct from the high finishing temperature of forging, is one of the energy saving heat treatments. A disadvantage is that it results in degradation of impact toughness especially in low-alloy steels of relatively high Mn content. Ti treatment, which consists of controlling the amounts of Ti and N addition, solidifying in continuous casting process, and breaking down the blooms at appropriate temperatures, was found to improve the impact toughness of ausforged and tempered specimens through both preventing grain growth at forging temperatures and accommodating grain boundary segregation. Ti treatment was also applied to vanadium-containing steel subjected to air-quenching (air-cooling from the finishing temperature of forging), and a higher level of impact toughness was successfully achieved by air-quenching.

In order to investigate the corrosion resistance of organic composite-coated steel sheets ( OCS ) in a real automotive environment, many kinds of corrosion tests were performed on test pieces and real automotive doors. Tests with a corrosive solution including iron rust were introduced to simulate the real corrosive environment of automotive doors. The relationship between the components of OCS and the corrosion resistance in the rust-including tests was examined. In addition, electrochemical studies were performed. Results indicate OCS has much better corrosion resistance than plated steel sheets with heavier coating weight in all tests. OCS shows excellent corrosion resistance in rust-free corrosive solution, however, some types of OCS do have corrosion concerns in rust-including tests. It became clear that these OCS types have an organic coating with lower cross-linking.