Department of Foundry and Strengthening Technologies, Federal State Autonomous Educational Institution of Higher Education “Ural Federal University named after the first President of Russia B. N. Yeltsin”, Ekaterinburg, Russia:

A. V. Sulitsin, Assistant Professor, e-mail: kafedralp@mail.ru
R. K. Mysik, Professor
S. V. Brusnitsyn, Professor

The paper is concerned with the technological peculiarities of wire rod producing out of oxygen-containing copper by continuous casting and rolling. Pouring defects which have an impact on the copper wire rod quality are listed. There was shown that gas pores in a cast billet are among the main causes for appearance of cracks in the copper wire rod. Such cracks are bringing out in the course of the standard wire rod twist test with the following untwisting. There has been studied the behavior of the gas pores arising from continuous casting process in an oxygen-containing copper billet for the ensuing rolling into wire rod. There has been fulfilled a metallographic analysis of cast and rolled billets, selected along the full length of rolling mill. It is determined an average size of pores which are not completely healed during plastic deformation and exert influence upon formation of cracks in wire rod. In the paper, there has been studied how the main copper melt gasing sources in case of the Controid wire rod manufacturing process influence on the probability of gas defects appearance in a continuously cast billet. Metallographic analysis of the continuously cast billet samples has been carried out. Average size of gas pores and porosity volume fraction have been determined. The hydrogen content in copper estimation procedure with due regard for gas pores volume fraction has been proposed. The hydrogen content in the continuously cast billet samples was determined depending on the different process variables of melt preparation for continuous casting. Besides, there was fulfilled the quality analysis of copper wire rod obtained under different process variables. Results of the fulfilled research testify that the moisture presented in the nitrogen gas injected into the melt is of considerable importance in the process of copper melt saturation by hydrogen. Adjustment of the continuous casting process regulations has allowed diminish probability of cracks appearance on copper wire rod during standard twist testing with subsequent untwisting.

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