| In recent years, with the increasing demand of lead-free and environmental materials, new types of communication function materials including dielectric, piezoelectric and ferroelectric materials are in the focus of people's researches. Rare-earth niobate ceramics with general formula LnNbO4(Ln represent La to Lu including Y) is a series of new functional microwave dielectric ceramic materials ,which has a ferroelastic phase of monoclinic structure at ambient temperature with similar structural phase transition characteristics, belongs to the perovskite scheelite class(ABO3). Their location of A or B can be replaced by other hydroniums with different radius and electrovalency to a certain extent, individually or in the compound. Thus, we can regulate the properties of material for different use. This paper is focus on replacing the location A with Yb or Ce, adding YNbO4 synthesized before, preliminary study their synthesize technology, microscopic structure and dielectric properties of relations and so on.The main raw materials applied are ytterbium oxide (Yb2O3) and niobium oxide (Nb2O5). YbNbO4 were obtained with molar rate of Yb2O3:Nb2O5=1:1, sintering of non-protected atmosphere through two technics "pre-sintering and then second sintering" and "In-situ synthesis". We obtained YbNbO4 ceramic with dielectric constant 26, Q value of 3.38×104 at sintering temperature 1360℃.Doped with Bi2O3, YbNbO4 were studied on its sintering behavior, crystal structure and dielectric properties. The results showed that the sintering temperature is lowed to some extent, yet the influence of Bi2O3 to the dielectric properties is not very obvious.Next, using the cerium oxide (CeO2) and niobium oxide (Nb2O5), we got the ceramics of CeNbO4+δ (δ=0-0.25) and some unknown phases with the molar rate of CeO2 :Nb2O5=1:1 and CeO2 :Nb2O5=2:1. CeNbO4+δ is very sensitive to environmental oxygen. Their crystal transformation, microstructure and change of dielectric properties were investigated.
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