Sintering behavior

The intrinsic properties may be modified by substitution (31). Ba can be fuUy replaced by Sr or Pb and partly by Ca (<40 mol %). CaM, stabilized with 0.03 mol % La202, is also possible. The intrinsic properties of these M-ferrites vary somewhat and other factors such as sintering behavior and price of raw materials often dictate the commercial viabiUty. Large-scale production is concentrated on BaM and SrM. High quaUty magnets are generally based on SrM, and somewhat lower priced magnets are based on BaM. 

Characterization studies of the final materials are also examined in order to clarify the relevant properties for high-temperature combustion, including detailed structural features and their relation to sintering behavior and combustion activity and role and nature of transition metal ion in the structure. 

The structural features of hexaaluminates, their sintering behavior, and their catalytic properties associated with the nature of the transition metal ion are discussed in detail in the following section. 

The crystal structure and the sintering behavior of hexaaluminates was widely investigated. The relation of sintering resistance to anisotropic ion diffusion in the layered alumina phase was clarified to a large extent. Other evidence suggests that combustion activity is obtained through a redox mechanism associated with reversible variation of oxidation state of the transition metal ions in the structure. Mn was the best and most stable active component. However, fundamental and applied studies are needed to better clarify the redox mechanism of the reaction and how it is related to the chemical and structural features of the Mn-containing layered-alumina phase. This could also provide useful information for the development of an optimum catalyst composition,... 

Raj, R. and Bordia, R.K. Sintering behavior of bi-modal powder compacts , Acta Metall. 32 (1984) 1003-1019. 

Fig. 5.10 A monolayer of 700 pm. diameter Polymethyl methacrylate (PMMA) beads during a sintering process at 203°C, x 50. (a) After 25 min (b) after 55 min. [Reprinted by permission from M. Narkis, D. Cohen, and R. Kleinberger, Sintering Behavior and Characterization of PMMA Particles, Department of Chemical Engineering, Technion Israel Institute of Technology, Haifa.]...

J.5. Effects of additives, promoters, and poisons on sintering behavior... 

The surface properties of carbon play an important role in the dis persion and the sintering behavior of supported catalyst. The study of iron-phthalocyanine is of particularly interest for the investigation of catalyst-carbon support interactions. The coalescence of PcFe particles on graphitized carbon is considerably lowered by the... 

Mackenzie K.J.D, Temuujin J., Jadambaa T.S., Smith M.E., Angerer P., Mechanochemical synthesis and sintering behavior of magnesium alummate spinel. J. Mat. Science 2000 35 5529-35. 

The size distribution of particles in a wide variety of particulate systems is of paramount importance in the chemical processing industries. For example, the compacting and sintering behavior of metallurgical powders, the flow characteristics of granular material, the hiding power of paint (qv) pigments (qv), and the combustion efficiency of powdered coal (qv) and sprayed fluids, are all heavily influenced by the size of the constituent particles (see Flow... 

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