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Lead Zirconate Titanate (PZT) ceramics are of great technological interest because of their excellent piezoelectric and ferroelectric properties. In this research, an effort will be made to enhance the PZT properties by doping with other elements. The objective of this research is to enhance the dielectric, hence increase the efficiency and performance of piezofan. Properties that piezoelectric fan should have are high mechanical piezoelectric coupling factor, high dielectric constant, easily polarized and high piezoelectric charge constant. Soft and isovalent dopant was a very suitable candidate to fulfill this requirement. The samples will be prepared via high planetary mill and use optimum compaction pressure due to these processes can skip calcinations process, which can reduce a lot of cost. This process also can avoid PbO loss during firing process. The proposed elements are isovalent dopant which is Sr2+ and donor dopant which is La3+ to subtitude Pb2+ at the A-site of PZT. Dopant is beneficial to the enhancement of physical properties of PZT – based ceramics. It also effectively improved the dielectric properties of PZT ceramics due to the effect of average grain size.

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Alkaline niobate known as K 0.5 Na 0.5 NbO 3 (KNN), a lead-free piezoelectric ceramic was synthesized via a solid state reaction method. The samples were compacted at different pressures (100, 200, 300 and 400 MPa) and sintered using two different techniques (conventional furnace and hot isostatic pressing (HIP)). The effect of compaction pressure and sintering technique on physical and dielectric properties was studied. The optimum compaction pressure (300 MPa) and sintering via HIP (at 1080°C for 30 min) increased the density and grain size (range 30-300 nm) and improved its dielectric properties. Therefore, the combination of suitable compaction pressure and sintering technique has produced larger grain size and higher density of KNN which resulted in outstanding dielectric properties. At room temperature, excellent values of ɛ r (5517.35) and tan δ (0.954), recorded at 1 MHz were measured for the KNN300HIP sample with highest density (4.4885 g•cm-3).