Preparation of La2NiMnO6 Double-perovskite Ceramics by Plasma Activated Sintering

Abstract

La 2 NiMnO 6 (LNMO) double-perovskite ceramics are normally prepared by the conventional pressureless sintering technique, which is difficult to produce dense structure and usually needs high sintering temperature as well as long sintering period. In this study, highly-dense La 2 NiMnO 6 ceramics with good performance were prepared by a novel Plasma Activated Sintering (PAS) method. The influence of PAS parameters, including sintering temperature and pressure, on crystalline phase, microstructure, relative density and dielectric properties of the LNMO ceramics were systematically studied by the means of XRD, SEM, Archimedes method, and impedance analyzer. The results showed that the crystallinity and grain size of the LNMO ceramics increased with the increase of sintering temperature, but the impurity phases might emerge if the sintering temperature further increased above 1000 ℃. The sintering pressure had little effect on crystalline phase, while the relative density of the LNMO ceramics could be effectively enhanced with the sintering pressure increasing. LNMO ceramics in single orthorhombic structure with relative density of 92% and giant dielectric constant (~10 6) were successfully obtained at the optimum PAS conditions, i.e., sintering temperature of 9751000 ℃ and sintering pressure of 80 MPa. Compared to the traditional pressureless sintering, LNMO ceramics

Elaboration and Characterization of WMoTaNb High Entropy Alloy Prepared by Powder Metallurgy Processes

“…The passage by the liquid state is not necessary, which makes it possible to control the microstructure of the part and, thus its properties. This technique is used on many materials, not only metals [ 26 , 27 , 28 , 29 ]. One of the major differences from other techniques is the efficiency of the heating.…”

The influence of DC pulse current pattern on the different materials properties of samples obtained by spark plasma sintering

“…The temperature in the spark discharge zones is in the order of about 1000 °C, which leads to local melting and/or evaporation of the raw material in very short periods of time. This leads the formation of a neck in the contact zones between the powder particles due to the mass transfer process [1][2][3][4][5][6][7][8]. For this reason, the study of the influence of the pulse current form on the mechanical properties of sintered samples is a very interesting field of research, which requires a lot of attention due to its practical application.…”

A review of fabrication and properties of spark plasma sintered tungsten carbide based advanced composites

“…[50][51][52][53][54][55] The SPS is also named as plasma activated sintering, pulsed electric current sintering, or field assisted sintering technique. [59][60][61][62][63][64] The ceramic community has recently given it a new title of current activated pressure assisted densification. 65 Owing to the commercial application and rapid development of SPS technique, a growth in the number of research papers including an important publication in nature 66 from year 2000 onwards is clearly observed (Figure 2(a)) 67…”