Cross machine investigation of magnetic tokamak dust; structural and magnetic analysis

Magnetic dust collected from multiple fusion devices (FTU, Alcator C-Mod, COMPASS) that feature different plasma-facing components (PFCs) and toroidal magnetic fields has been analyzed by means of the X-ray diffraction technique aiming to investigate nature origin magnetism. Analysis led conclusion main mechanism ferromagnetic formation is change iron crystalline phase austenitic ferritic during re-solidification stainless steel droplets. also revealed differences in structure an unexpectedly high amount based its native phase. Theoretical estimates showed moment force can mobilize strongly paramagnetic adhered prior establishment proper tokamak discharges. The post-mortem analysis pure discharges FTU confirmed these estimates.