EFFECT OF LEAD CONTENT OF ZINC BATH ON FORMABILITY AND MECHANICAL PROPERTIES OF HOT-DIP GALVANIZED STEEL SHEETS

摘要

In this study, the effect of lead content of zinc bath on the formability of hot-dip galvanized steel sheet was evaluated using uniaxial tensile test and forming limit diagram (FLD). For all specimens, elongation, work hardening exponent, anisotropy, yield strength and tensile strength were measured by uniaxial tensile test and FLDs were also sketched. FLDs were obtained using an electrochemical etching technique for printing the circular pattern and specimens with different widths in dry and lubricated conditions were deformed using a hemispherical punch. Strains were measured using Miller ruler. From the experimental results, it was concluded that by increasing the lead content of zinc bath the value of FLD_o s decreased because of decreasing the active slip planes; this in turn caused reduction of coating formability.