Phosphate Bonded Monolithic Refractory Materials with Improved Hot Strengths as a Potential Replacement for Phosphate Bonded Bricks
The phosphate bond generally provides a lower modulus of elasticity compared to more brittle conventional cement and ceramic bonded materials. The flexible bonding mechanism results in higher impact resistance. Moreover, phosphate bonded materials show excellent resistance to aluminium metal penetration and corundum growth. In addition, phosphate bonded bricks with low alkali content possess high hot strengths at elevated temperatures which can significantly increase their performance against mechanical abuse. Based on this information a project was started to develop phosphate bonded monolithic materials with similar or better physical and chemical properties than phosphate bonded bricks but with the advantage of installation characteristics of conventional cement bonded materials. Additional goals were to use a water based system and minimize restrictions on installations techniques. Flow and working time should be similar to conventional monolithic materials, making this material as versatile as possible. In order to achieve these goals extensive tests were carried out in collaboration with independent research laboratories and as a secondary step, some of the new formulations were installed in severe environment applications with high mechanical abuse and chemical attack. The development process and the physical and chemical properties of a new phosphate bonded monolithic material will be shown in context with available literature and in comparison with test data of phosphate bonded bricks and conventional cement bonded materials. The results of field tests and potential new applications will also be presented.
A.Prasad, J.A. Taylor and J.F. Grandfield
J. Decker "Phosphate Bonded Monolithic Refractory Materials with Improved Hot Strengths as a Potential Replacement for Phosphate Bonded Bricks", Materials Science Forum, Vol. 693, pp. 90-103, 2011