Measuring adhesion of microparticles in lunar regolith simulant BHLD1000 by centrifugal technique

Abstract

The adhesion of lunar material is strong and harmful to the functional surfaces of spacecraft systems. Using lunar regolith simulant instead of rare real one to understand the adhesive property of lunar regolith is an economical approach. In this work, we firstly introduced a theoretical model of the adhesive behavior between lunar regolith simulant micro-particle and different aerospace materials. In this model, total adhesion force is determined by Van der Waals force, electrostatic force and capillary force. Surface energy, surface potential, particle size and inertia force are the key factors affecting adhesion. Then we designed an experimental method using centrifugal technique and image processing to quantify and visualize the adhesion effect. By using a newly developed lunar regolith simulant BHLD1000 and four types of aerospace functional surfaces, we found the size of adhesive micro-particles are a few micrometers and the adhesion forces on them are a few nN on average. This experimental value is three orders of magnitude smaller than the theoretical one (several μN) due to particle irregularity and surface roughness. The adhesion model, the experimental approach and measurement results developed here are useful in understanding the real adhesion of lunar regolith on the moon as well as designing dust-proof tools for future lunar explorations. • An adhesion model between lunar regolith simulant and typical aerospace materials is proposed. • Lunar regolith simulant BHLD1000 with a wide particle size distribution is developed for experimental study. • High Speed centrifuge technology with specially-made accessories is used to help quantify the adhesion indirectly. • Optical microscopy with picture processing is discussed to embody the particles detaching manner statistically. • Adhesion force between BHLD1000 and typical aerospace materials is evaluated in laboratory environment.