High temperature excursions have the potential to strongly enhance the room temperature adhesion of tokamak dust. Planar tungsten substrates containing adhered nearly monodisperse spherical tungsten dust have been exposed to linear plasmas and vacuum furnaces. Prolonged thermal treatments of varying peak temperature and constant duration were followed by room temperature adhesion measurements with the electrostatic detachment method. Adhesive forces have been observed to strongly depend on the thermal pre-history, greatly increasing above a threshold temperature. Adhesive forces have been measured up to an order of magnitude larger than those of untreated samples. This enhancement has been attributed to atomic diffusion that slowly eliminates the omnipresent nanometer-scale surface roughness, ultimately switching the dominant interaction from long-range weak van der Waals forces to short-range strong metallic bonding.

高温游览有可能极大地增强托卡马克粉尘在室温下的附着力。含有粘附的几乎单分散的球形钨粉尘的平面钨基材已暴露于线性等离子体和真空炉中。在峰值温度和恒定持续时间变化的长时间热处理之后，采用静电分离法进行室温粘附力测量。已经观察到粘合力在很大程度上取决于热前史，大大超过阈值温度。测得的粘合力比未经处理的样品高出一个数量级。这种增强归因于原子扩散，原子扩散缓慢消除了无所不在的纳米级表面粗糙度，