Sintering solid-state powder

In sintering, the green compact is placed on a wide-mesh belt and slowly moves through a controlled atmosphere furnace (Fig. 3). The parts are heated to below the melting point of the base metal, held at the sintering temperature, and cooled. Basically a solid-state process, sintering transforms mechanical bonds, ie, contact points, between the powder particles in the compact into metallurgical bonds which provide the primary functional properties of the part. 

In this chapter shock modification of powders (their specific area, x-ray diffraction lines, and point defects) measurements via analytical electron microscopy, magnetization and Mossbauer spectroscopy shock activation of catalysis, solution, solid-state chemical reactions, sintering, and structural transformations enhanced solid-state reactivity. 

The defects of the matrix play an important role on luminescent performances in these materials. Taking into consideration the preparation process of these compounds with the solid-state reaction of mixtures of BaC03, H3BO3, and NH4H2PO4 at different molar ratio, non-equal evaporation during the sintering process of these powders is inevitable and thus results in the formation of intrinsic defects, such as cation and oxygen vacancies. Positional disorder of B and Vacant B (Vb)" have been reported in SrBPOs crystals on the basis of... 

N. Senamaud, D. Bernache-Assollant, E. Champion, M. Heughebaert, C. Rey, Calcination and sintering of hydroxyfluorapatite powders. Solid State Ionics 101-103 (1997) 1357-1362. 

Most modern materials are formed empirically by solid-state methods. These methods generally involve more processing activity than chemical synthesis (for example, sintering of ceramic powders, modifying concrete by polymers, thermomechanical processing of alloys, layering polymeric membranes for... 

The kinetic transport mechanisms that permit sintering are solid-state processes, and therefore sintering is an important forming process that does not require melting. Materials with high melting temperatures, such as ceramics, can be molded into a complex shape from a powder and subsequently sintered into a solid body.13... 

G.C. Kuczynski. Theory of solid state sintering. In W. Leszynski, editor, Powder Metallurgy, pages 11-30, New York, 1961. Interscience Publishers. 

POWDER METALLURGY. Powder metallurgy (PM) embraces the production of finely divided metal powders and their union through the use of pressure and heat into useful articles. The temperatures required are below the fusion point of the principal constituent, and bonding depends on interdiffusion of the metal particles in the solid state. It is necessary to provide intimate contact between particles, hence reducing atmospheres are provided in the sintering process to prevent formation of oxide films Readily oxidized powders such as aluminum require special technique. 

Solid-state diffusion of carbon, nitrogen, or both carbon and nitrogen, into titanium powders at high temperatures (1270-1770 K) where the reaction takes place over the course of several hours.8-12 TiCN can also be produced by sintering a mixture of TiC and TiN 13 or by solid-state diffusional reactions in the systems of TiC + N2, TiN + C, and Ti + C + N2.14,15... 

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