| At the present time in China, the proportion is quite high for Ni containing austenitic stainless steels in all stainless steel products. However, China is a country lacking of Ni resources, which is causing serious problems to the production and application of stainless steels. Therefore, the production policy must be adjusted to develop high performance ferritic stainless steels in order to support the sustainable development of the economy. Currently, the proportion of ferritic stainless steel are accounting for as much as 40% in Japan and Korea. As previewed by specialists of Japan, the proportion of ferritic stainless steel will surpass 70% of all stainless steel products in 2012.This paper, based on ultra-purified ferritic stainless steel, mainly investigated the effect of microalloying Nb and Ti on the proportion of equiaxed grain in solidification. In addition, the typical steels were chosen to take the rolling experiment, and then, the excellent formability performances were obtained by optimizing all procedure. The texture evolution was analysised by XRD in all procedure.(1). In all investigated steels the microstructure is single ferrite phase during high temperature region after solidification. The increase in content of carbon, titanium and niobium would lead to the increase in the equiaxed grain proportion for the experimental heats. TiN precipitated in liquid steel could act the inhomogeneous nucleus for the subsequent solidification of the equiaxed grains. The final equiaxed grain proportion was determined completely by the content of precipitation TiN. The precipitation behavior for the second phases is mainly dependent on their solid solubility product in steel. In addition, Titanium nitride particles were observed in both steels with the size of around 3μm at grain boundary or within grains by the analysis of SEM.(2). The steel No.3 (Nb=0.29%,Ti=0.09%) and No.4 (Nb=0.40%,Ti=0.07%) were chosen to investigated the mechanical performance in all the procedure by the change of finishing temperature. The test results showed that r-value of No.3 was higher than that of No.4 in formability of finished product sheets, and r-value obtained in steel taking the finish temperature 940℃was higher than in steel taking the finishing temperature 890℃. Moreover, it could be concluded that when cold band was cold rolled with a thickness reduction of 80%, the average r-value was notably highest, r=1.46. The plastic anisotropy of a sheet is judged ofΔr,Δr=-0.14. Furthermore, IE-value was measured to arrive 9.8mm, and LDR-value was 2.1(3). While complete recrystallization structure cannot be obtained by box-annealing, the best system was established by the continuous annealing. In steel No.3, it was continuous annealing for 6 min at 1050℃when taking finishing temperature 940℃and for 9 min at 1000℃when taking 890℃. In addition, both steels were recrystallization annealed for 6 min at 1050℃in steel No.4.(4). The texture, during the hot rolling, box annealing, cold rolling and continuous annealing, was determined by means of X-ray texture analysis. It mainly consisted of the a-fiber orientations with fairly intensity distribution along the fiber after hot rolling or cold rolling. Besides, the intensity of a-fiber is not weak evidently after box annealing. Note that the texture maximum is appreciably shifted by about 8°from {111}<112> on theγ-fiber to an orientation with{334}<483>.(5). The texture, for the finishing temperature 940℃, was investigated during the course of hot-rolling continuous annealing. While the recrystallization temperature was 950℃, the strong a-fiber turned out to remain very stable, and then, it grew weak with the annealing temperature increasing and the time extending. The intensity of a-fiber was weakest when temperature got 1050℃, which meaned that recrystallization was sufficient. In addition,γ-fiber was found after full annealing in steel.
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