Synthesis and Characterization of Scandia Doped Nano Tungsten Powders
摘要
Scandate Cathodes have the potential to replace conventional M-Type dispenser cathodes due to their improved emission characteristics such as high emission current density (Top Layer-Laser Ablation Deposition: 1–400 A/cm2) [1], lower operational temperatures (750–950 ℃) [2], and longer lifetime (10,000 h). In the present work, Scandate doped Tungsten nano powders are synthesized by Liquid-Liquid method using Sol-Gel chemical route process [3]. Synthesized powders are characterized for particle size, shape, crystal structure and elemental composition. Powder X-ray diffraction (XRD) is employed to analyze the crystal structure, phase formation and average particle size. Transmission Electron Microscope (TEM) is used to analyse nano particle structure and crystalline size. The powders are pressed into 7 mm diameter pellets using hydraulic press followed by sintering. Scanning Electron Microscope (SEM) is used to capture surface morphological images like pore size, pore distribution and distribution of Scandium oxide on Tungsten particles. Uniform distribution of the ingredients on the pellet surface is confirmed by Energy Dispersive X-ray analysis (EDAX). These analysis helped to understand the properties of synthesized powders and to optimize the synthesis process.