Deuterium retention in various toughened, fine-grained recrystallized tungsten materials under different irradiation conditions

Deuterium retention in two types of toughened, fine-grained recrystallized W (TFGR W-1.2 wt% titanium carbide (TiC) and TFGR W-3.3 wt% tantalum carbide (TaC)) was studied, compared to pure W. D plasma exposure was performed to a fluence of 1 × 10²⁶ D m^-2 at a temperature of 573 K, followed by retention measurement analysis by nuclear reaction analysis and thermal desorption spectroscopy (TDS). It is found that D retention in TFGR W is higher than that in pure W. This is because TFGR W has a high density of trapping sites with low trapping energy and dispersoid (TiC or TaC) may serve as additional trapping sites with high trapping energy. Different irradiation experiments (D ion beam implantation) were also conducted at sample temperatures of 473-873 K, followed by TDS. At higher sample temperature (> 700 K), D retention in TFGR W-3.3 wt% TaC is lower than that in TFGR W-1.2 wt% TiC. This may be due to different types of dispersoids.