Damage mechanism of blast furnace tuyere by zinc

ABSTRACT

A damaged tuyere from a practical blast furnace was sampled. The microscopic structure was investigated using a metallurgical microscope. The chemical analysis and mapping were investigated by a scanning electron microscope with energy spectrum analysis. Meanwhile, line scanning electron microscope with energy spectrum analysis was applied to investigate the change of content of copper and zinc from hot surface to the interior of copper matrix of the damaged tuyere. The results show that an alloy layer of about 2 mm in thickness appears on the hot surface of the damaged tuyere manufactured from pure copper, and the size of grains increases compared with the new tuyere. The content of zinc in the alloy layer decreases with spreading into the copper matrix. ExpAssoc function fits well with the variation of thermal conductivity of the alloy, and the thermal conductivity decreases with increasing zinc content in the alloy layer.

KEYWORDS:

• Tuyere
• zinc
• thermal conductivity
• blast furnace

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The present work was supported by National Basic Research Program of China (973 Program) (No. 2012CB720401) and National Natural Science Foundation of China (CN) (No. U1260202).