The Effect of Drawing in Conventional and Hydrodynamic Dies on Structure and Corrosion Resistance of Hot-Dip Galvanized Zinc Coatings on Medium-Carbon Steel Wire

Abstract

The paper presents the impact of the drawing method on the microstructure and corrosion resistance of galvanized steel wires. The microstructural tests confirmed that, in the drawing speed range v = 5–20 m/s, the use of hydrodynamic dies creates more favorable conditions for the deformation of the soft zinc coating on the hard steel core. The increase in friction at the wire/die interface in the conventional method, as compared to the hydrodynamic method, contributed to the decrease in coating thickness and the increase in the diffusion layer, and the higher the drawing speed, the greater the differences between the analyzed drawing methods. In the conventional method, while drawing at high speeds v = 20 m/s, there was a two-way diffusion and complete remodeling of the ζ phase in δ1. In the hydrodynamic method, at the speed of 20 m/s, in the analyzed micro-areas, places showing the presence of the ζ phase, partially dispersed in the layer with pure zinc, were observed. A corrosion tests comparison between conventionally and hydrodynamically drawn wires showed an improved behavior of the latter. The greater mass in the surface layer of pure zinc, a substrate for the corrosion product in hydrodynamically drawn wires, reacted, creating insulation from the white corrosion produced. The compressive stresses in the hydrodynamic dies caused by the high pressure of the lubricant on the circumference of the wire closed the microcracks on its surface, which additionally sealed the zinc coating.

Microstructure and Corrosion Behavior of ZnAl12Mg3Si0.3 Double-Batch Hot-Dip Coatings

“…Hot-dip-galvanized (HDG) coatings are currently one of the most effective and economical corrosion protection methods for steel. Demand for zinc coatings is constantly growing, covering an ever-wider range of products, such as drawing wires [ 1 ], iron castings [ 2 ], and products from high-strength steel [ 3 ]. The HDG process currently consumes more than 50% of the world’s zinc production, with zinc production steadily increasing.…”

Effects of Contact Conditions at Wire–Die Interface on Temperature Distribution during Wire Drawing

“…The softened materials can be easily sheared and removed under frictional stress, resulting in high wear depth [48]. Therefore, to overcome this drawback, the research on the streamlined die [49,50], hydrodynamic lubrication [51,52], die coating [53], and ultrasonically oscillating dies [54][55][56] have been conducted in the wire drawing research fields. In addition, the frictional stress at the wire-die interface affected the material properties at the surface of the wire during wire drawing [57].…”

Influence of the Straining Path during Cold Drawing on the Hydrogen Embrittlement of Prestressing Steel Wires

“…FE simulations lead to a complete estimation of the residual stress and strains during the conformation process [5,[18][19][20]. New cold-drawing chain designs are developed with Metals 2023, 13, 1321 2 of 14 the aim of reducing the manufacturing-induced residual stress state, most of them by modifying the die geometry [18][19][20][21][22][23][24][25]. In [5,26,27], multistep dies were analyzed, considering multiple reductions in the same die.…”