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چکیده
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This research has studied the impact of transformation-induced plasticity on the tensile properties and anisotropy of work-hardened 304 and 304L stainless steel sheet samples. For this purpose, cold rolling was carried out with up to 40% reduction in thickness to produce strain-induced a¢-martensite. The optical metallography, XRD, and feritscope testing were used to study the microstructures of the specimens before and after cold rolling operation. It was observed that 304 stainless steel samples showed a higher volume fraction of a¢-martensite than 304L samples, i.e., 0.456 and 0.321 for 304 and 304L samples, respectively. This is due to the strain-induced martensitic transformation after 40% cold rolling and the lower SFE in 304 stainless steel. In addition, uniaxial tensile testing was carried out to study the tensile properties and anisotropy of the specimens. Anisotropy coefficients were calculated for solution treated, 20% and 40% cold rolled sheet samples from the tensile tests with respect to the rolling, diagonal and transverse direc- tions. Transformation-induced plasticity in the 304 and 304L samples resulted in a reduction in normal anisotropy, which reduces the deep drawability. The calculated normal anisotropy in 304 samples was less than 304L due to the higher volume fraction of a¢-martensite in 304 samples. Therefore, it is predicted that the cold-rolled 304L samples would show higher deep drawability compared to 304 samples.
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