Effect of Reaction Temperature on Pickling of 430 Stainless Steel
stainless steel is used as raw material and pickling in HCl-based electrolytes is adopted, and the effect of pickling temperature on removal behavior of the oxide layer on stainless steel is systematically studied, study found that the oxide layer of stainless steel after heat treatment in the lab is composed of Fe2O3 and Cr2O3, at different temperatures, with the increasing of duration, corrosion potential of stainless steel after heat treatment shows fall followed by rise, and corrosion potential of stainless steel in 60°C is obvious higher than in 50 °C; with temperature increasing, the weight loss of stainless steel after pickling increase with large range, and the weight loss of the oxide layer of stainless steel increases as the duration increases.
A Study of the Scale Structure of Hot-Rolled Steel Strip by Simulated Coiling and Cooling
The morphological development of oxide scale on hot-rolled steel strip under various simulated coiling and cooling conditions was investigated. Oxide-scale structures developed were classified into several categories, and the conditions under which each category formed were identified and mapped. It was found that oxide scale formed under normal coiling and cooling conditions had a structure that was difficult to pickle. Increased cooling rate after coiling, or coiling at a temperature below 350°C, improved this structure. The conditions under which a magnetite layer at the wüstite–steel interface was formed during continuous cooling were also identified and the mechanisms of its formation discussed.
The new continuous cold rolling and annealing line of Ugine at Isbergues (France)
The steps of the conventional production process of stainless steel cold rolled strip are recalled, as well as the evolutions that have preceeded the design of the LC2i line. The advantages and constraints of this integrated and continuous line are outlined. The main equipments coupled in the line are described and their characteristics presented. Automation, work force training, TPM, protection of the environment have been essential features in the project.