Properties of tungsten-rhenium and tungsten-rhenium with hafnium carbide

Abstract

Research Summary Refractory metals ResearchHow would you… …describe the overall signifi cance of this paper?This paper describes the processing and properties at elevated temperatures for tungsten-rhenium and tungsten-rhenium with hafnium carbide. Tungsten-25% rhenium has an elastic modulas of greater than 400 GPA and an ultimate tensile strength exceeding 280 MPa at 1,921ºC. A novel material with hightemperature strength is described.…describe this work to a materials science and engineering professional with no experience in your technical specialty?High-temperature refractory metals for high-temperature applications are described in this paper. …describe this work to a layperson?This material is a structural component at 2,000ºC.

Ion-irradiation-induced clustering in W–Re and W–Re–Os alloys: A comparative study using atom probe tomography and nanoindentation measurements

“…As well as causing large degrees of cascade damage (up to 20 displacements per atom per full-power year) [3], the neutron irradiation will cause pure tungsten to transmute into Re and subsequently Os, yielding potential solute contents as high as 3.8 at.% Re and 1.38 at.% Os after 5 years of reactor operation [4]. Although the equilibrium W-Re-Os phase diagram predicts complete solubility at this composition [5], the mechanical properties of components could be severely degraded due to the formation of irradiationinduced solute-rich clusters as the precursors to sigma and chi precipitates [6,7]. Previous studies of the irradiation responses of these systems are sparse and limited to compositions with more than 3 at.% rhenium and/or osmium present [8][9][10][11].…”

Hardening of self ion implanted tungsten and tungsten 5-wt% rhenium

“…Gilbert and Sublet [11] have calculated that pure tungsten would transmute into an alloy of composition W-3 at%Re-1.4 at%Os after 5 years in an operational reactor. The tungsten-rhenium phase diagram is complex, showing several intermetallic phases [12]. Of particular interest are the r-phase, present above $30%Re and $5% Os on equilibrium phase diagrams, and the v-phase, centred around $72%Re [12,13].…”

“…The tungsten-rhenium phase diagram is complex, showing several intermetallic phases [12]. Of particular interest are the r-phase, present above $30%Re and $5% Os on equilibrium phase diagrams, and the v-phase, centred around $72%Re [12,13]. While these phases are thermodynamically expected for relatively high Re content, they have been observed in neutron-irradiated under-saturated W-5%Re and W-25%Re alloys using transmission electron microscopy (TEM) [14] and field ion microscopy [15,16].…”

“…Thus it is of critical importance that the mechanical properties of irradiated tungstenrhenium alloys be understood. Additionally it is well known that additions of rhenium while in solid solution improves the ductility of the material [12,20]; however due to the high cost and scarcity of rhenium [20] the use of W-Re alloys is not seen as a viable route for the construction of a divertor structure.…”

A Comparison of Materials Issues for Cermet and Graphite-Based NTP Fuels

“…Recently, elastic-plastic properties for W /25Re ( [26] and Figure 8), W-50%UO 2 [5], ZrC ( [19], [20], and Figure 10), and (U,Zr)C-graphite ( [9] and Figure 9) have been researched and incorporated. This allows better detection of yielding and fracture.…”