Effect of clay functionally graded materials on dual gradient direct ink writing behavior and microstructure of geological model

Abstract

Purpose The study aims to explore the composition and microstructure of clay functionally graded materials under the process of double-gradient direct ink writing (DIW). Design/methodology/approach The investigation focused specifically on the pore characteristics of barite-kaolin clay composite after three-dimensional (3D) printing and sintering as well as its bionic application in geophysical model. Findings The model with pore and material variations brought about spatial and nonlinear mechanical properties. Moreover, the vertical gradient and connected pores in the upper kaolin part simulated the natural phenomenon of the landslide model (take Chinese Majiagou landslides as an example). Both the thermal debinding behavior and the kaolin powder particles characteristics [large pore volume (0.019 cm3g–1) and pore size (29.20 nm)] were attributed to the interconnection channels. Originality/value Hence, the macroscopic and microscopic pores achieved by dual-gradient DIW process make it possible to control the permeability and details of properties, precisely in the geological model.