Abstract: Adhesion between deep-sea sediment and metal surface were studied using the deep-sea sediment collected from the Pacific C-C Zone (Clarion-Clipperton Zone), under different void ratios, normal pressures and loading speeds. A formula for calculating top soil adhesion index between deep-sea sediment and metal surface is developed based on the calculation of separating force of parallel disc. This research selects four commonly used marine metals (aluminium alloy 5052, titanium TA2, titanium alloy TC4 and titanium alloy STi80). INSTRON 5943 universal testing machine was used for the adhesion tests. The results show that the adhesion force increases with a high growth rate, as the void ratio of soil sample increases. As the normal pressure increases, the topsoil adhesion index increases exponentially. As the loading speed increases, the topsoil adhesion index decreases gradually. And the adhesion between deep-sea sediment and 5052 or STi80 are weaker. The results provide an important theoretical basis for the safe of deep-sea mining in China.

Key words: Pacific C-C Zone, deep-sea sediment, soil-metal interface, adhesion characteristics