Effect of reduction-slagging coupling of Cr2O3 during in-situ preparation of homogeneous CuCr50 alloy by self-propagating high temperature synthesis metallurgy

Abstract

The high-efficiency separation of alloy and slag is fundamental to obtain high-performance CuCr alloys by self-propagating high temperature synthesis metallurgy. In this paper, Cr2O3 can determine the basic composition of CuCr alloy through the reduction efficiency, and also participates in the slagging process, which determines the separation effect of slag and alloy. Therefore, the reduction behavior and slagging effect of Cr2O3 during the in-situ synthesis of CuCr alloy by aluminothermic reduction is investigated. The results show that the Cr content of the prepared CuCr alloy is 41.3 wt.%∼42.0 wt.% according to the theoretical stoichiometric ratio, and the Cr2O3 content in the slag is 16.2 wt.%∼17.0 wt.%. When the Cr2O3 dosage is 50% over the theoretical stoichiometric ratio, the Cr content of the prepared CuCr alloy and the Cr2O3 content in the slag increases to 47.0%∼47.6 wt.% and 28.4 wt.%∼29.2 wt.%, respectively. With the increase of Cr2O3 dosage in the ingredients, the effect of alloy-slag separation is better, the inclusion in the alloy changes from Al2O3 inclusion to Cr2O3 inclusion, and the relative density of prepared CuCr alloy increases from 90.9% to 98.5%. The overall composition is evenly distributed among the different parts of the alloy. The conductivity of CuCr alloy reaches 15.69 MS m−1, and hardness reaches 95.1 H B.

Keywords

• CuCr alloy
• Aluminothermic reduction
• In-situ synthesis
• Cr2O3 slagging
• Self-propagating high temperature synthesis metallurgy(SHS-Metallurgy)