Introduction

In the divertor of reactor-class tokamaks such as ITER and DEMO understanding the sputteringand re- depositionis critical. Tungsten can be tolerated in only very small quantities in the plasma core before fusion power is degraded.Tungsten will be eroded by the fuel ions and impurities, but due to its large Larmor radius is likely to be locally(promptly) re-deposited. In conditions where the plasma is also high density re-deposition can also occur due to friction between the sputtered tungsten and the ions. Recent results in Magnum-PSI experiments have indicatedthat the re-deposited tungsten can form a layer with different microstructure and properties than the bulk tungsten. Such a layer could be at risk of delamination and flaking into the core plasma, which could cause a disruption. This project aims to further understand the re-deposition process and the properties of the re-deposited material.

Your Project

Using Magnum-PSI you will study the sputtering and re-deposition of tungsten in high-density plasmas. The re-deposited material will be characterized using, for example, nano-indentation and scanning electron microscopy. You will study the thermomechanical response of the re-deposited layers to thermal transients to investigate how they behave under representative loading. This will give important information about the expected formation and performance of the re-deposited tungsten layers.

What we offer

• Access to top class facilities and instrumentation at DIFFER like Magnum-PSI and the Ion Beam Facility
• Supervision and guidance that aims to support you while letting you be in charge of the project
• A PMI group team of enthusiastic and knowledgeable students around you
• Limitless free coffee!