Sintering shrinkage curve

The size distribution of the powder particles (crystallite clusters which are kinetically independent units in a suspension), and other characteristics, are given in Table 1. The green body pores size distribution is given in Fig. 2. The sintering shrinkage curves (5°C/min) are shown in Fig. 3, while the evolution of BD as a function of the sintering temperature (3 h dwell at peak temperature) is given in Table 11. 

Figure 7.12 Shrinkage curves (dropping from left to right) and temperature schedules (rising from left to right) for sintering under a linear temperature control of 15°C/min (solid line) and under a linear shrinkage rate control of 0.005 in/min (dotted line). [14]...

Figure 1 shows shrinkage curves of metals Ml(Mo), M2(Mo with 0.1mass%Ni) and ceramics Cl(Zr02), C2(PSZ) calculated by Eqs. (1) (4), which are employed as components of FGM. The rate of heating up is 100°C/min. After the temperature reaches 1400 °C, the sintering is carried on at the same temperature for one hour. The material parameters used in Eqs. (1) (4) are shown in Table 1. These component materials were referred to the research on molyb-... 

Let us express the shrinkage behavior of powder mixtures MCI composed of Ml and Cl, and MC2 composed of M2 and C2 by the shrinkage curve of each component shown in Figure 1. It is assumed that there is no reaction between the metals and the ceramics. The powder mixtures are described as two porous bodies mechanically engaging with each other. Using this assumption, the sintering stress of the mixtures may be given by... 

Figure 10.4 Typical axial shrinkage curves during sintering as a function of temperature, where T,. > T,.

A schematic of a typical shrinkage curve for the three phases of sintering is shown in Fig. 10.25 (note the log scale on the. v axis). Relative to the other two processes, particle rearrangement is the fastest, occurring in the time scale of minutes. The other two processes take longer since they depend on diffusion through the liquid or solid. 

Figure 11.33 Isothermal shrinkage data for constrained and free glass films sintered at 650°C. The curve through the data for the free film represents the best fit to the data using Scherer s model for viscous sintering. The curve through the data for the constrained film represents the fit to the data by the thin-fihn model of Scherer and Garino using the fitting constants derived from the fit to the free-film data. (From Ref. 47.)...

Figure 12.3 Sintering curves for ZnO in air during constant heating rate sintering at 5°C/min obtained from the dilatometric shrinkage curve showing (a) the shrinkage and density as a function of temperature and (b) the densification rate as a function of temperature.

Figure 12.7 Natural logarithm of the shrinkage versus the reciprocal of the temperature for a multicomponent gel during constant heating rate sintering calculated curves (MODELED) and measured data (MEASURED). (From Ref. 5.)...

Figure 24 Shrinkage curve for AIN sintered with Y2O3 and low temperature firing compositions.

The shrinkage curve recorded during an isothermal treatment of liquid phase sintering shows three stages ... 

The minimum porosity is attained at the ratio where the voids between the coarse particles are completely occupied by the finer partices. As follow s from Fig. 153, this is the case at about 70% of the coarse fraction. A sliarp minimum would be attained at a very high ratio of particle sizes. In fact, the behaviour of volume moves along the indicated curve, since the ratio of particle sizes attainable docs not usually exceed 1 10 in practice. With binary mixes, it is possible practically to attain a porosity of 25%, and for ternary mixes, 22%. This corresponds to a volume shrinkage of 22 — 40%, i.e. linear shrinkage 7—13 i - for sintered products. Theoretically, it should... 

On the basis of regression curves one can determine the content of zirconium phase at which sinters based on hydroxyapatite show zero shrinkage. In the case of HAp + Z1O2 (8%wt. Y2O3) ceramics, a simple extrapolation method enabled determination of Zr02+8%wt. Y2Ch powder content which ensured zero shrinkage at the level of 70.6% wt. Content interval determined from confidence corridor amounts to from 65% to 76% wt. 

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