Influence of electric current on interdiffusion kinetics of W-Ti system during spark plasma sintering. (September 2018)

• Record Type: Journal Article
• Authors: Deng, Shenghua; Yuan, Tiechui; Li, Ruidi; Zhang, Mei; Xie, Siyao; Wang, Minbo; Li, Lanbo; Yuan, Jiwei; Weng, Qigang
• Is Part Of: International journal of refractory metals & hard materials. Volume 75(2018)
• Page Start: 184
• Page End: 190
• Publication Date: 2018-09
• Subjects: Interdiffusion -- Electric current -- Spark plasma sintering -- Tungsten -- Titanium; Heat resistant alloys -- Periodicals; Refractory materials -- Periodicals; Metallography -- Periodicals; Alliages réfractaires -- Périodiques; Matériaux réfractaires -- Périodiques; Métallographie -- Périodiques; Heat resistant alloys; Metallography; Refractory materials; Periodicals; Electronic journals; 669.73
• DOI: 10.1016/j.ijrmhm.2018.04.014
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: The effect of electric current on the atomic diffusion of W-Ti system using spark plasma sintering (SPS) was investigated. The interdiffusion coefficient of W-Ti system during SPS was observed to be higher compared to that in the traditional sintering. The electromigration effect was observed in W-Ti system and an improved kinetics model was applied to reveal the role of electric current in atomic diffusion kinetics. It was found that the interdiffusion coefficient increased with increasing current density, while the activation energies were constant. This phenomenon is mainly because the atomic moving velocity is accelerated by the electron wind force in the direction of electron flow, but the diffusion mechanism remains unchanged, resulting in the invariability of activation energy of binary substitution-diffusion. Additionally, the interdiffusion coefficient is independent of the pulse pattern but strongly relies on the effective current density, implying the main acceleration mechanism of pulse current remains to be electromigration. Highlights: The impact of current on diffusion kinetics was studied quantitatively by using improved model. The phenomenon caused by electromigration was explained from a physical perspective. It was proved that the main acceleration mechanism of pulse current remain to be electromigration. A diffusion kinetics equation incorporating pulse parameters was established.