On the Structural and Chemical Homogeneity of Spark Plasma Sintered Tungsten

Autor: Jiří Matějíček, Monika Vilémová, Jakub Veverka, Jiří Kubásek, František Lukáč, Pavel Novák, Dalibor Preisler, Josef Stráský, Zdeněk Weiss
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Metals, Vol 9, Iss 8, p 879 (2019)
Druh dokumentu: article
ISSN: 2075-4701
DOI: 10.3390/met9080879
Popis: Tungsten-based materials are the prime candidate plasma-facing materials for future fusion reactors, such as DEMO. Spark plasma sintering is a prospective fabrication technology with several advantageous features. The concurrent application of electric current, temperature and pressure enhances the sintering process, allowing for lower temperatures and shorter sintering times than traditional powder metallurgy processes. This in turn helps to avoid excessive grain growth and phase segregation in W-alloys. This study is focused on several factors that may influence the homogeneity of the sintered compacts—namely the diffusion of carbon from the graphite die, purity of the powder and sintering conditions. The following characteristics of spark plasma-sintered tungsten compacts were studied: composition (especially carbon and oxygen content), porosity, mechanical properties (hardness and fracture strength), and thermal diffusivity. The effects of the abovementioned processing factors were quantified, and local variations of selected properties were assessed.
Databáze: Directory of Open Access Journals