Micro-arrayed stretch drawing process of nanocrystalline Ni-Co foils with soft-male-die

A novel micro forming method, combining arrayed forming and soft-die forming, has been developed for manufacturing micro stretch drawing parts from nanocrystalline Ni-Co foils. In this study, nanocrystalline Ni-Co foils were prepared by electrodeposition and a series of micro-arrayed stretch drawing experiments with soft-male-die (5083 aluminum) were conducted by using these foils. The as-deposited Ni-Co material has smooth surfaces and uniform sized grains, and the roundness and surface quality of stretch drawing parts are satisfactory. Experimental results indicate that the die size, forming temperature and foil thickness have significant effects on the stretchability of the Ni-Co foil. And the maximum height-to-diameter ratio was obtained when the diameter of female die, forming temperature and foil thickness were 800 μm, 823 K and 60 μm, respectively. The micro-arrayed stretch drawing technology has prospects for industrial applications because of the significantly improved efficiency and comparatively high formability.