Hyogo-ken, 651 Japan.An 80kgf/mm' grade high-strength hot rolled sheet steel with a significantly high product of tensile strength and total elongation (TSxEl=3000) has been developed by utilizing

The changes in recrystallization behavior and 7-value by reducing impurity elements in Ti-added ultra low carbon sheet steel were investigated. The recrystallization temperature of high-purity steel is lower than that of conventional impure steel whencomparedat a given finish-rolling temperature or solute titanium content. This is attributed to the retarding effect of phosphorus, which can be interpreted on the basis of a commonly accepted solute-drag effect since sulfur and nitrogen have almost no effect on recrystallization behavior.The half-recrystall ization temperature of Ti -added ultra low carbon steel is more closely related to the content of solute titanium, rather than the amount of The data concerning steel C8, symbolized with mark e, highly deviates from the relation between carbon content and half-recrystallization

No abstract

On the'other hand, in the steels of group S(S1-5), Ti was Annealing SimulationCold-rolled steels were annealed in the infrared-ray heating furnace. Figure I shows

The mechanical properties of low carbon steel sheets produced through the process of rapid solidification casting, cold rolling, and annealing are studied for the purpose of developing sheets with deep drawability by a strip casting method. For a continuously annealed low carbon Al-killed steel sheet, a treatment for grain-refinement of the rapidly-solidif fled plate is favorable to render the r value and tensile properties comparable to the products of conventional continuous casting process. Batch annealed low carbon Al-killed steel sheets produced from the rapidly-solidified plate show good drawability, even though the cast plate has a coarse acicular ferrite structure.