Adjusting trace element limits while maintaining properties (SPÅRA)

Purpose and goal

Steel grades contain many alloying elements and also unwanted trace elements and contamination elements, which give the material its properties. Undesirable elements can be partly handled metallurgically to reach standards for products or additional requirements based on gained experience of negative impact on properties. These elements originates from the starting materials like scrap, and can be reduced to varying degrees and complexity in metallurgical processes. Copper is difficult to reduce, and it is therefore of interest to evaluate which levels can be accepted.

Expected effects and result

Since copper cannot be separated in normal metallurgical processes, the content must be reduced by dilution. This affects the circularity negatively, and it would be desirable to have a higher tolerance of copper and thereby save a larger proportion of scrap. The industrial benefit is primarily to improve the supply of raw materials with clearer information regarding the impact of copper on product properties, which is a common interest for all parties, and which the project intends to evaluate.

Planned approach and implementation

With a background from strategic analysis and state of knowledge regarding current standards, the impact of copper must be tested. First, a broader investigation with small-scale testing in lab operations with small ingots (2-12kg) and small-scale testing. Then a large-scale pilot operation with ingot 50-270kg, and also full-scale testing with associated application-close evaluation. The work will be a close collaboration between all parties, for both the production of materials and the evaluation of properties.