Kurzfassung

In steel ladles refractory linings are exposed to severe working conditions. The thermal shock that typically occurs when a ladle is refilled at the converter has a tremendous impact. The temperature increases from 1000 C to almost 1700 C within seconds. This is one reason why the linings of the working zone are realized with MgO-C materials, because they provide a highly elastic carbon based bonding system compared to ceramic bond materials. There is a strong demand from the industry to...In steel ladles refractory linings are exposed to severe working conditions. The thermal shock that typically occurs when a ladle is refilled at the converter has a tremendous impact. The temperature increases from 1000 °C to almost 1700 °C within seconds. This is one reason why the linings of the working zone are realized with MgO-C materials, because they provide a highly elastic carbon based bonding system compared to ceramic bond materials. There is a strong demand from the industry to provide carbon free materials for steel ladles or comparable applications that can be installed as a monolithic material. The advantages are obvious: Monolithic materials allow a more rapid installation of steel ladles and consequently downtimes can be reduced to a minimum.
Alumina based spinel containing or spinel-forming monolithics are already state of art for the lining of steel ladles. However, in comparison to MgO-C materials, their durability is limited and poor.
At present it is difficult to provide a target oriented research work on the durability of alumina based monolithics, because a key parameter cannot be investigated properly. There is no analytical technique to test the thermoshock resistance at high temperatures as they occur in steel ladles. Standardised methods that test between 1000 °C and room temperature are not reasonable, because ceramic bond materials behave brittle at room temperature and develop distinct elastic properties with increasing temperatures.» weiterlesen» einklappen