Transient grating spectroscopy of thermal diffusivity degradation in deuterium implanted tungsten

Abstract

Graphical AbstractAbstract Using transient grating spectroscopy, we measure thermal diffusivity and surface acoustic wave speed in tungsten exposed to different fluences of deuterium plasma. Scanning electron microscopy (SEM) shows the formation of surface blisters that have similar morphology for all fluences considered. A significant reduction in thermal diffusivity and surface acoustic wave speed occurs as a result of plasma exposure. A saturation of the thermal diffusivity reduction with fluence is seen. Deuterium ion flux density appears to play a more important role in thermal diffusivity reduction than exposure time. These observations have important implications for plasma facing components in future fusion reactors.

Non-contact, non-destructive mapping of thermal diffusivity and surface acoustic wave speed using transient grating spectroscopy

“…4. There are a number of examples for this, 13,15,16,22 with custom routines in MATLAB frequently being used to do the fitting.…”

“…Detailed results of this study are provided in Ref. 16. Here, the same sample is used to illustrate the 2D mapping capability of the TGS setup.…”

“…[31][32][33] Our previous work showed a significant degradation of thermal diffusivity and reduction in SAW speed in the exposed area. 16 Using the mapping capability of the TGS setup, we have measured a map of thermal diffusivity and SAW speed that spans the entire sample [Figs. 6(d) and 6(e)].…”

“…[10][11][12] Thermal diffusivity measurements from TGS have been used to detect the presence of crystal defects and impurities in metals, 13 as well as to monitor irradiation-induced microstructural evolution, for example, in single-crystal niobium 14 and tungsten. 13,15,16 TGS presents several key advantages over other more conventional thermal diffusivity and acoustic property measurement methods: it is non-contact, non-destructive, and quite rapid (<2 s for a spot measurement). The only requirement for the measurement is a flat sample surface polished to a mirror finish.…”

Investigation of Phase Transformation of Fe65Ni35 Alloy by the Modified Pulse Method

“…Thermal diffusivity is an important thermodynamic property because it is suitable for predicting material behavior in many heat-transfer applications. Reza et al [ 3 ] used this parameter in deuterium-implanted tungsten investigations. Bellucci et al [ 4 ] used thermal diffusivity in research on graphene nanoplatelets using the pulse method.…”