Description

The relationship between the amount of cold work, surface roughness, and thickness of delta phase (FeZn) for very short dipping times was investigated. It was shown that the thickness of delta phase is dependent on the surface condition and particularly the surface roughness of steel. The smaller the roughness average (Ra), the thinner the delta phase would be. A decrease in the total amount of cold work or light drafts during the final passes of wiredrawing can help to reduce the roughness average. Lighter cold work or annealing seems to help reduce the delta thickness by reducing the Ra.