Reactive sintering liquid phase

Reactive liquid-phase sintering, 5 661 Reactive molecules, oliigonucleotides conjugated to, 17 636-637 Reactive organic phosphorus compounds, 11 496-497... 

Effects of particle size and pressure on the reactive sintering were studied by Gobran et al. (2004). The synthesis of RuAl was described it was observed that reactive systems containing low-melting constituents such as aluminium are assisted in densification by the formation of a transient liquid phase. Reactive sintering using... 

Gas-solid reactive sintering can also be used in the oxidation of most metals or, more important, mixtures of metals. After oxidation, solid state sintering takes place. With mixtures of metals, a mixed oxide is produced which can be sintered by either solid state or liquid phase sintering. One example of alloy oxidation to produce a ceramic is in the synthesis of the superconductor YBa2Cu3Q. ... 

Prior to the sintering and annealing operations in the fabrication of electrolyte tubing, the green-formed shapes are bisque-fired (<1200°C) to remove binders and lubricants During reactive liquid phase sintering of / "-alumina at 1575-1585° C, four processes normally occur in parallel " ... 

PuOj from direct calcination of Pu(N03 )4. The precipitation steps of the above processes can be avoided by the direct calcination of the plutonium nitrate solution to PuOa. Calcination has been carried out at 350 C in a liquid-phase screw calciner. Half a mole of ammonium sulfate per mole of plutonium is added to the feed solution to increase the production of reactive PuOi. The calcination time and temperature must be low enough to minimize sintering, which would otherwise reduce the chemical reactivity of the oxide particles for subsequent conversion to a halide. 

The manufacturing process (especially the cold and hot compaction stages) of pcBN is very similar to that of pcD, summarized in Section 1.3.3. However, the types of binders used and liquid phase sintering mechanisms can be quite different. In pcBN production, reactive sintering plays a major role in terms of driving the densification process, whereas in pcD, dissolution and precipitation and/or adhesion/coalescence are the main driving mechanisms. A typical example for pcBN would be the following reaction [162]. 

Figure 5.14. Part of the phase diagram of Si/Mo indicating possible reaction paths (arrows) of reactive liquid phase sintering of molybdenum disilicide. If the reaction heat increases the temperature the solid does not form during sintering and the whole mixture melts.

Using liquids such as molten salts or water under hydrothermal conditions as the reaction medium Liquid-phase reactive sintering is also an example of the use of a liquid phase to increase the reaction rate. 

In reactive liquid sintering, due to reduced sintering temperatures ( transient liquid phase sintering ). 

Kinetics of the liquid-phase reactive sintering of silicon carbide , Poroshk. Metall. 5, 35-43. 

---