Effects of self-healing biomimetic subsoiler on tillage resistance, wearcorrosion performance and soil disturbance morphology under different soil types

Subsoiling has been widely used all over the world as an important operation method of no-tillage farming.For energy-saving and life-extension,the tillage resistance and wear-corrosion of subsoilers have attracted wide attention.In this study,the tillage resistance,soil disturbance,wear and corrosion of subsoiler with S-T-SK-2#biomimetic structures(S means subsoiler;T means tine;SK means shank;2#,h/s=0.57,h=5 mm andα=45°.)and self-healing coating under two seasons,two locations with different soil properties(black loam and clay soil)and subsoiling speeds(2 km/h and 3.6 km/h)were investigated.The soil moisture content and compactness affected the tillage resistance and wear-corrosion.The tillage resistance and degree of corrosion on all subsoilers were much larger in clay soil than that in black loam soil.Compared with S-T-SK-2#,the tillage reduction rate of C-S-T-SK-2#(S-T-SK-2#with self-healing coating)was up to 14.32%in clay soil under the speed of 2 km/h.The significance tests of regression equation results showed that subsoiler type and soil properties had a significant impact on soil disturbance coefficient,swelling of total soil layer,bulkiness of the plough pan.It is of a guiding significance for the analysis of soil disturbance.Synergism mechanism of subsoiler coupling with biomimetic structures and self-healing coating was analyzed in following.It depicted the guiding effect of biomimetic structure and the shield function of self-healing coating,resulting in anticorrosion and wear resistance of subsoiler.

Effects of Biomimetic Surface Designs on Furrow Opener Performance

The effects of biomimetic designs of tine furrow opener surface on equivalent pressure and pressure in the direction of motion on opener surface against soil were studied by finite element method (FEM) simulation and the effects of these designs on tool force and power requirements were examined experimentally.Geometrical structures of the cuticle surfaces of dung beetle (Copris ochus Motschulsky) were examined by stereoscopy.The structures of the cuticle surfaces and Ultra High Mo- lecular Weight Polyethylene (UHMWPE) material were modeled on surface of tine furrow opener as biomimetic designs.Seven furrow openers were analyzed in ANSYS program (a FEM simulation software).The biomimetic furrow opener surfaces with UHMWPE structures were found to have lower equivalent pressure and pressure in the direction of motion as compared to the conventional surface and to the biomimetic surfaces with textured steel-35 structures.It was found that the tool force and power were increased with the cutting depth and operating speed and the biomimetic furrow opener with UHMWPE tubular section ridges showed the lowest resistance and power requirement against soil..