| Cold-rolled sheet steel for automobiles requires high strength and good drawability, for that purpose P-bearing low carbon, low maganese Al-killed steel is investigated. For various coiling temperatures on hot rolling stage, the effects of coiling temperatures on textures and deer-drawability of P-bearning steel were investigated by 1) pole intensity analysis 2) Transmission Electron Microscopy 3) plastic strain ratio determination from tensile test. No apparent changes in textures of hot-rolled sheet and cold-rolled sheet were detected within the range of coiling temperatures examined. The optimum coiling temperature for good recrystalization texture, high average strain ratio (R) and low planar anisotropy (ΔR) after recrystallization annealing was 600℃. However, differences in their characteristics were very slight except the specimen of coiling temperature 700℃ However, since the maximum tensile strength of the specimen was obtained when coiled at 600℃, optimum coiling temperature which could provide good deep-drawability while sustaining high strength might be concluded to be around 600℃ in this steel. |
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