Showing 3 results for Ghassemi Kakroudi
M. Ghassemi Kakroudi,
Volume 5, Issue 4 (Autumn 2008 2008)
Abstract
Abstract: Refractory materials containing cordierite (2MgO.2Al2O3.5SiO2) and mullite (3Al2O3.2SiO2) are used as
support in furnaces, because of their low thermal expansion properties which confer them a very good ability to
thermal shock resistance. Composed of two phases presenting very different CTE (1.5–3×10-6 for cordierite and
4–6×10-6 K-1 for mullite), these materials can develop damage during thermal cycling due to internal stresses.
The resulting network of microcracks is well known to improved thermal shock resistance of materials, since it usually
involves a significant decrease in their elastic properties. This paper is devoted to the characterisation of the damage
generated by this CTE mismatch, thanks to the application of a specific ultrasonic device at high temperature.
M. Farzalipour Tabriz, M. Ghassemi Kakroudi*,
Volume 7, Issue 4 (Autumn 2010 2010)
Abstract
Abstract: Cordierite-Mullite based kiln furnitures are widely used in fast-firing of ceramic products because of their low thermal expansion which confer them a very good ability to thermal shock resistance. Difference in CTE of constituent phase can develop damage during thermal cycling due to internal stresses. Increase in industrial competitiveness leads to the development of new means for extending refractory life and increasing reliability of industrial tools so investigations regarding the structuralmechanical behaviour of refractory systems are becoming essential. In this paper, Thermo-mechanical design of commercial Cordierite-Mullite based kiln furniture was investigated by using finite element method (FEM) and possible solutions for improvement of working life have been considered. The results indicated that the change of the kiln furniture geometry can decrease the maximum thermomechanical stress in study conditions which can prolong the refractory service life. Obtained results indicate the existence of an optimal thickness for the section under maximum thermo-mechanical stress. Increasing filet radius of ring region from 3 to 9 mm decreases thermo-mechanical stress value from 113 to 93 MPa.
H. Safabinesh, A. Arab Fatideh, M. Navidirad, M. Ghassemi Kakroudi,
Volume 11, Issue 3 (september 2014)
Abstract
In order to improve the corrosion resistance of aluminosilicate refractories by molten aluminum, alkaline
fluoride NaF and cryolite Na3AlF6 powders were studied. Both physical and chemical properties are known to
influence wetting and corrosion behavior. This paper devoted to determine the influence of alkaline fluoride and
cryolite added to andalusite based castable on the reaction with aluminum alloys. These additives led to the in-situ
formation of celsian phases within the refractory matrix that led to improved corrosion resistance at 1300°C. Phase
analysis revealed that celsian formation suppressed the formation of mullite within refractories, thereby reducing
Penetration
