Fabrication Of Hollow Microlattice And Study On Its Mechanical Performance

Hollow microlattices is a kind of super-material with ultra-light,ultrastiff,ultra-strong and ultra-energy absorption ability.At present,the material is still in the laboratory development stage.The strength and density can not achieve the ideal linear relationship yet.It is necessary to study the key technology of fabrication of the microlattice material,and then analyze its mechanical properties and failure mechanism.It is of great significance to optimize the coating technology and microstructure design to make the material reach its target performanceIn this paper,a comparative study of various fabrication technologies of hollow microlattice material was firstly made.A set of complete and independent fabrication process based on SLA technology and chemical plating craft was conducted.Secondly,some in-situ compressive tests were carried out to investigate the mechanical behavior of hollow microlattice under compression.Then,a mechanical model was constructed to simulate the failure process of the hollow microlattice.Through experimental tests and numerical simulation,the compressive failure mechanism of nickel hollow microlattice material were discovered.The effects of different coating materials,different coating thickness and different coating technology on the material properties were analyzed.Combining the microscopic observation and the stress nephogram analysis of model,the deformation process and failure mechanism of the material during compression were investigated.Finally,the key micro-structural characteristics that affect the material properties were determined.It was found that the hollow microlattice material fabrication in this study can achieve a substantially constant stress until the compressive deformation reaches 80%.However,the specific strength is still lower than expected.The thickness of the coating has a significant effect on the failure mechanism and the stress-strain curve under static compression.Coating quality and microstructure characteristics are two major factors affecting the properties of hollow microlattice material.