| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
|
| Symposium
|
Advanced Characterization of Materials for Nuclear, Radiation, and Extreme Environments
|
| Presentation Title |
Femtosecond Laser Induced Surface Damages in Tungsten and Tungsten Carbide in High Heat Flux Conditions |
| Author(s) |
Minsuk Seo, Shukai Yu, Venkatraman Gopalan, Leigh Winfrey |
| On-Site Speaker (Planned) |
Minsuk Seo |
| Abstract Scope |
Tungsten is a divertor material for the tokamak fusion reactor, and tungsten carbide could be a potential material. Tungsten and tungsten carbide were irradiated by high heat flux (59.6GW/m2) femtosecond laser with different angles (0°, 30°, 45°, 60°) up to ~5000 shots in ambient air to emulate surface damages by hypothetically synchronized edge localized modes (ELMs) and loss of vacuum accident (LOVA). The surface crater contained laser-induced periodic surface structure (LIPSS), grooves, and morphologies were changed by laser influence spatially and angularly. The periods of low spatial frequency LIPSS (LSFL) have increased, and high spatial frequency LIPPS (HSFL) has decreased for both tungsten and tungsten carbide surfaces as the incident angle increased. The high-temperature surface oxides were detected by linear energy dispersive spectroscopy (EDS). The possible oxide forms are tungsten oxide, cobalt oxide, or cobalt tungstate, all potentially detrimental to nuclear fusion operation. |