本研究利用水熱法合成鈮酸鉀與鈮酸鈉，再將鈮酸鉀與鈮酸鈉以等莫耳比例混合燒結製成無鉛壓電陶瓷K0.5Na0.5NbO3 (KNN)。將不同量的KNN粉末與壓電高分子P(VDF-TrFE)混進丁酮溶液製備成漿料，再利用由工程積木組件自製的3D列印機印製出可撓性無鉛壓電複合材。
壓電複合材以P(VDF-TrFE)壓電高分子為基材，其中包埋KNN壓電陶瓷顆粒。KNN粉末粒徑在10 μm以下。壓電複合材整體厚度介於30~50 μm。經FTIR量測可知摻雜KNN有助於引致P(VDF-TrFE)的壓電性β晶相形成。將不同漿料印製成的壓電複合材依序經過乾燥、退火、極化處理，進行D33量測與落球衝擊試驗量測輸出電流，兩者的實驗結果展現相似趨勢。KNN的D33約82 pC/N；P(VDF-TrFE)之D33約24 pC/N。複合材的D33皆介於P(VDF-TrFE)與KNN之間，摻雜2 wt% KNN漿料印製成的樣本經極化處理後產生最佳的壓電表現 (D33約59 pC/N)，摻雜3 wt% KNN 漿料印製成的樣本僅需經過乾燥處理就有相對優異的壓電表現(D33約51 pC/N)。本實驗之原料設計彈性、電腦輔助工程及小批量生產的特性，在講求客製化製造型態的工業4.0時代中極具發展潛力。

KNbO3 and NaNbO3 micron-sized particles were synthesized by hydrothermal process, then the equimolar KNbO3 and NaNbO3 were mixed and sintered into (K0.5Na0.5)NbO3 (KNN). KNN particles were mixed with P(VDF-TrFE) in MEK as slurry for 3D printing. Flexible lead-free piezoelectric composites were printed by a homemade 3D printer.
Piezoelectric composites were composed of KNN piezoelectric ceramic particles dispersed in P(VDF-TrFE) piezoelectric polymer matrix. The size of KNN particles is limited within 10 μm, and the thickness of printed piezoelectric composites is within the range of 30 to 50μm. FTIR results of composites show that the addition of KNN particles induces the crystallization of P(VDF-TrFE) piezoelectric β-phase. Printed composites were further processed in order of drying, annealing and poling treatment. Then the piezoelectric parameters D33 of composites undergone different treatment were measured. Drop-impact test was also conducted to measure the current output performance of composites. The results of D33 and current output show similar trends. The D33 value of composites is between synthesized KNN (~82 pC/N) and P(VDF-TrFE) (~24 pC/N). The composites made of slurry containing 2 wt% KNN show the highest D33 (~59 pC/N) after annealing and poling. The dried composites made of slurry containing 3 wt% KNN without any heat treatment show relatively excellent piezoelectric performance (D33~51 pC/N). The features of slurry design flexibility, computer aided engineering and batch production of this research are promising in industry 4.0 era.

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