Anisotropy of fracture mechanical properties of carbon-containing refractories and its impact on cracking in a steel ladle lining

Abstract

Cracks are occasionally observed in bricks installed in steel ladle sidewalls. Three magnesia-carbon refractories used in steel ladles were investigated in terms of the anisotropy of the mechanical properties and their possible contribution to crack formation. The main differences between these bricks were the direction of the moulding force and the type of press used (spindle or hydraulic press). This study aimed to clarify the reasons for the inferior performance of one refractory material compared to other materials from a thermomechanical point of view. The results showed clear anisotropy in the elastic and fracture mechanical data. Brittleness was the lowest and crack propagation resistance was the highest when the crack extended parallel to the moulding force. Therefore, the lowest cracking vulnerability was observed in the case of a moulding force perpendicular to the longest brick edge and this was verified via field observations.

Keywords

• Magnesia-carbon refractories
• Specific fracture energy
• Anisotropy