Metamaterial: Smart Magnetic Material for Microwave Absorbing Material

In this research, CoFe2-xLaxO4-based smart magnetic material has been developed which will be applied as a microwave absorbing material. This smart magnetic material is an artificial advanced material which has properties such as electromagnetic waves so that it is able to respond to the presence of microwaves through the mechanism of spin electron resonance and wall resonance domain. This smart magnetic material consists of a combination of rare earth metal elements (spin magnetic in the f orbital configuration) and transition metal elements (spin magnetic in the d orbital configuration) with a semi-hard magnetic structure. This semi-hard is a characteristic of magnetic properties which is between hard magnetic and soft magnetic properties. This characteristic of the semi-hard magnetic properties is needed so that this material has the ability to absorb microwaves. Substitution of lanthanum into cobalt ferrite CoFe2-xLaxO4 for La3+ (x = 0 - 0.8) has been synthesized using the solid reaction method through mechanical deformation techniques. The refinement result of X-ray diffraction shows that the sample contains 2 phases with increasing of x compositions. Particle morphology and elementary analysis were observed respectively by using a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). It was concluded that the effect of La substitution on CoFe2-xLaxO4 resulted in changes in the crystal structure parameters and phase transformation as a function of composition.

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Synthesis and characterization of structural and magnetic properties of graphene/hard ferrite nanocomposites as microwave-absorbing material

Journal of Materials Science ◽

10.1007/s10853-014-8676-3 ◽

2014 ◽

Vol 50 (3) ◽

pp. 1201-1213 ◽

Cited By ~ 73

Author(s):

Zehra Durmus ◽

Ali Durmus ◽

Huseyin Kavas

Keyword(s):

Magnetic Properties ◽

Synthesis And Characterization ◽

Absorbing Material ◽

Structural And Magnetic Properties ◽

Microwave Absorbing

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The Effect of Additive on Temperature Rising Characteristics during Coal Pyrolysis in Microwave Field

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.1790 ◽

2012 ◽

Vol 512-515 ◽

pp. 1790-1794

Author(s):

Quanrun Liu ◽

Hao Xia

Keyword(s):

Heating Rate ◽

Microwave Field ◽

Pyrolysis Temperature ◽

Coal Pyrolysis ◽

Final Temperature ◽

Absorbing Material ◽

Microwave Absorbing ◽

Rapid Pyrolysis

The pesent paper decribed the effects of additive on temperature rising characteristic during coal pyrolysis at different temperature in microwave field. Different mixture rate of carboncoal with coal and different final temperature on coal pyrolysis tempereature rising characteristics were studied in the work. The results indicate: Coal is a poorly microwave absorbing material, and its pyrolysis in microwave field need to add a certain amount of microwave absorbent for higher heating rate; Because carbocoal can be fast heated in microwave field, so it can be used as additive for coal pyrolysis. Carbocoal otained from different pyrolysis temperature have different heating rate, along with the increase of carbocoal pyrolysis temperature, carbocoal heating rate increases in microwave field. Using charcoal as microwave absorbent for coal rapid pyrolysis in microwave field is feasible.

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