Liquid phase sintering solution/reprecipitation

Fig. 5.43 The three mechanisms of grain-shape accommodation and neck growth during solution reprecipitation controlled densification of liquid-phase sintering a contact flattening, b dissolution of small grains, and c solid-state bonding. Reproduced with permission from [73]. Copyright 2009, Springer...

Kur] Kuroki, H., Han, G., Shinozaki, K., Solution-Reprecipitation Mechanism in Fe-Cu-C During Liquid Phase Sintering , Int. J. Powder Met., 35(2), 57-62 (1999) (Phase Relations, Thermodyn., Calculation, 14)... 

The mechanisms of liquid-phase sintering processes have been described in detail by Kingery (213, 214], Petzow (215), and German [216]. The sintering process can be treated as a sequence of three stages particle rearrangement solution-reprecipitation and skeleton sintering. 

Both modifications a and /i are present in different amounts in the starting powder (Table 10) mostly a-rich powders are used. At sintering temperature the metastable a-phase and the subcritical /i-particles (dcrit <0.5 pm) dissolve in the liquid and reprecipitate during cooling as /i solid solutions on the initial stable /1-particles which act as nuclei, while the homogeneous and heterogeneous nucleation can be neglected in most cases (Sect. 6.1). 

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