Preparation Of Nanocrystaline Ni-Co/GO Foil Material And Research Of Micro Super Plastic Forming

In recent years, nano-material has been widely studied due to its specialstructure, the super molding performance of which has become a hot spot in thefield of scientific research. Graphene has opened up many new application fields indirection of composite materials for its unique mechanical, physical and chemicalproperties. At the same time, the development of MEMS makes the study of microforming more and more important. In this paper, Ni-Co/GO foils was prepared bypulsed electrodeposition, then studied the impact of graphene oxide additives (GO)content, foil thickness on the mechanical properties at room temperature,high-temperature plasticity and organizational structure. The paper studied thematerial superplastic forming ablity by micro hemisphere bulging test at hightemperature. Design high-temperature microarray deep drawing experiments toexplore the feasibility of forming more smaller parts.By controlling the deposition time and the content of the GO, preparednanocrystalline Ni-Co/GO foil, the thickness of which are from10to210μm andthe content of GO are0,0.01,0.05,0.1g/L. With SEM, we observed the smoothand dense surface, and the surface brightness levels increased with GO reduced. ByTEM and XRD measured the grain size computing device15~50nm.Tensile experiments at room temperature were carried out to study foil fracturestrength at room temperature of different thickness at70、140、210μm and thecontent of GO of0,0.01,0.05,0.1g/L. The fracture strength of the materialincreased with the increase of the thickness, the addition of GO content, and themaximum fracture strength is1154MPa. Microhardness study of materials showthat with the increase of GO content, micro hardness of the material increases. Withhigh-temperature tensile test measured that the material have the best plastic at500℃, the plastic decreases with the increase of GO, the test got the maximumelongation of500%at500℃when excluding GO.At500℃for GO content of0g/L,0.05g/L and0.1g/L of foil gas microhemisphere bulging experiments, bulging height greater than2.5mm, and with GOcontent increases, bulging height decreasing bulging pressure increment, indicatingthat the material can achieve superplastic deformation and material strengthincreases with increasing GO. Bulging wall thickness distribution, SEM fracturesurface showed intergranular fracture.Designed5x5microarray diameter of0.36mm deep drawing dies, with foils thick of12~14μm, carried out the test at500℃and proofed the feasibility offorming more smaller parts.