Periclase



Chemical formula: MgO
Melting point: 2800oC
Density: 3.581 g/cm3
Microhardnes: 1000 kp/mm2
Hardness (Moh's): 6
Luminescence: Non-fluorescent, long uv=light yellow
Crystal system: Cubic
Cell dimensions: a=4.2 A
PDF number: 00-002-1207
ICSD number: 009863
Note: Periclase is an important structural component of several basic refractories. In magnesite brick it is usually visible as rather largem rounded grains, but the grain size depends upon firing temperature and brick composition and the priclase structure may be finner. Periclase is also a structural component of burnt dolomite.The priclase phase is visible as white-grey, rounded grains with an even surfaces. They remain unchanged in moist atmospheres, unlike CaO, the other main structural component, which is attacked. An example of periclase with dendritic morphology has been given by Brunner. Such dendritic periclase structures can be obtained upon cooling in refractories containing MgO which have been in contact with liquid CaO-SiO2 slag at high temperatures. A liquid slag rich in MgO forms on the surface of the refractory, dendritic periclase crystallizing from this slag on cooling.


Copyright © 2018 by Steel Data. All Rights Reserved.