## 3 Results
It should be noted that using the CCT (and not to HP as it is commonly assumed [16]) forms the most uniformly grained, close-packed structure with the crystallites of the regular geometric shape and the rectilinear boundaries in materials (Figure 2). Within the framework of the CCT, varying \(T_{sint. }\), \(\tau_{sint. }\) and the sintering conditions (in the backfilling of sintering product and without it), the influence of these parameters on the structure of PCR-13 was traced and we determined the optimal conditions for the preparation of the PCR-13. For each of the used technologies, a series of the images, \(8\div 10\) pieces each, were made. It was established that the highest reproducibility of the properties corresponds to the CCT. The Role of the Thermodynamic Pelistory in the Formation of the Internal Structure of the Samples Made Using Conventional Ceramic Technology  
Figure 3 shows the X-ray diffraction patterns of the PCR-13 material, which was sintered according to the CCT under various conditions (Figure 3a) and the X-ray fragments, including the lines (200)\({}_{c}\) (Figure 3b). It is seen in Figure 3a that there is a line at \(2\theta\ =\ 32.8^{\circ}\), the diffraction angle of which corresponds to the strong ZrO\({}_{2}\) line. This means a violation of the stoichiometry of the material towards an increase in the Ti concentration and a consequent shift into the T-region of the phase diagram of the PZT system. It can be seen in Figure 3b that the most homogeneous material was obtained at \(T_{sint. }\ =\ 1500\) K and \(\tau_{sint. }\ =\ 2\) h (X-ray diffraction pattern CCT4), with the same sample practically not containing ZrO\({}_{2}\). Table 2 shows the structural characteristics and density of the ceramic material PCR-13 under different sintering modes. It can be seen from the table that in the samples made in backfilling (CCT1-CCT3 samples), the degree of the T-cell distortion (\(c/a\)) is greater than in the samples produced by the HP, which indicates a greater shift of the first ones into the T-region. The density of the ceramic is higher in the samples obtained using CCT at 1500 K in the backfill for 5 h.  
Figure 3: X-ray diffraction patterns of PCR-13 material produced by CCT under different sintering conditions: CCT1 at \(T_{sint. }\ =\ 1520\) K for 2 h with backfill; CCT2 at \(T_{sint. }\ =\ 1500\) K for 2 h with backfill; CCT3 at \(T_{sint. }\ =\ 1500\) K for 5 h with backfilling; CCT4 at \(T_{sint. }\ =\ 1520\) K for 2 h without backfill; CCT5 at \(T_{sint. }\ =\ 1520\) K for 5 h without backfill (**a**); fragments of X-ray patterns, including lines (200)\({}_{c}\) (**b**). It can be seen that at \(2\theta~{}=~{}32.8^{\circ}\) (Figure 3a), there is a line, which has a diffraction angle that corresponds to the strong ZrO\({}_{2}\) line. This means a violation of the stoichiometry of the material, which increases the Ti concentration and consequently shifts it to the T-region of the PZT system phase diagram. As seen in Figure 3b, the most homogeneous material was obtained at \(T_{sint. }~{}=~{}1500\) K and \(\tau_{sint. }~{}=~{}2\) h (CCT3), with the same sample containing the smallest amount of ZrO\({}_{2}\). Table 2 shows the structural characteristics and density of the ceramic material PCR-13 under different sintering regimes. It can be seen that in the samples made in backfill (samples CCT1-CCT3), the degree of T-cell distortion (\(c/a\)) is greater than in the samples produced by the HP method, which indicates a greater shift of the former in the \(T\) region. The density of the ceramic is higher in the samples obtained at 1520 K in the backfill for 5 h.  
Figure 4 shows the fragments of the microstructures of the PCR-13 material obtained under various technological regulations, which also indicates that the optimal method to obtain the PCR-13 material is by using CCT at \(T_{sint. }~{}=~{}1500\) K and \(\tau_{sint.