MECHANICAL PROPERTIES IMPROVEMENT WITH GRAIN SIZE REDUCTION IN OPTIMAL ELECTRODEPOSITED METAL/POLYMER MICROTRUSSES

摘要

Metal/polymer composite structures can be fabricated by combining net-shape stereolithography methods with electrodeposition to create hybrid microtruss materials. These stretch-dominated lattice structures can be used in sandwich panels where the network of metal tubes provides a low density and high-strength core. By modifying the electrodeposition parameters, the grain size of the metal coating can be decreased, increasing its strength. While grain size reduction can increase the strength of the structure six-fold while maintaining the same mass, significant additional gains can be made by changing the structural geometry in tandem with the material properties. This study demonstrates the available improvement when an optimally designed polycrystalline Ni/polymer microtruss has its grain size decreased to the nanoscale. The improvements in mechanical properties will be compared to aerospace grade materials such as Ti-6%A1-4%V and Al 7075 T6.