Two grades of high strength deep drawing phosphorized sheet steel P1, P2, two grades of 08Al, and four kinds of galvanized sheet steel were examined in order to study on formability of new deep drawing sheet steel in Chinese automobile industry. The results show that the modified YBT-4, biaxial stretch of the square sample with Px = 2kN is the appreciate method for estimating ability of buckling resistance of the sheet steels. The ability to resist buckling of the sheet steel with higher yield strength is weaker than that of with lower yield strength. Compression is an effective method to remove buckling. The initial buckling height has no effect on the residual buckling height when the compression force is sufficient for complete yield of the buckled area. γ, δ_1, Al_5Fe_2 were found in the coating layer of the hot-dipped galvanized sheet by X-ray diffraction. The γ phase is acid－resistent and adheres steel base tightly due to existence of Al_5Fe_2. The δ_1 phase is very thin and no acid-resistant. The anisotropic ratios of the bare sheet and the stripped sheet with γ phase layer which were got after different treatments are higher than that of the as-received hot-dip galvanized sheet, whereas their limited drawing ratios decrease. There is a strong effect of friction on deep drawing ratio LDR of the hot-dipped galvanized sheet. The higher the friction coefficient is, the lower the LDR is. But the anisotropic ratio r has no effect on LDR of the galvanized sheets.
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