High plastic-strain ratio galvanized steel sheet and production method

The invention relates to a hot galvanizing sedan plate and the production method thereof, which solves the following problems: P and S in steel are difficult to control because of being lowly required; as to a horizontal Sendzimir hot galvanizing machine, the recrystallization temperature of a steel plate is slightly high, and the plastic strain ratio and extension are low. The high-plastic-strain-ratio galvanizing plate is composed of no more than 0.004% by weight of C, no more than 0.020% by weight of Si, 0.05% to 0.20% by weight of Mn, no more than 0.016% by weight of 0.016, no more than 0.015% by weight of S, 0.04% to 0.07% by weight of Ti, 0.02% to 0.06% by weight of Als, no more than 0.003% by weight of N, and the balance Fe and unavoidable impurity. The production steps are as follows: smelting by hot metal desulphurization and secondary refining process; hot rolling; cold rolling with a total reduction of 80%; and galvanizing. The invention has the characteristics that the method is pure Ti processing; the control scopes of S and P are wide; the plastic strain ratio is r90 DEG C >=2.5, the extension A80mm is 45% to 50%; and the current process route and equipment is unchanged.