Drawability of thin magnetron sputtered Al–Zr foils in micro deep drawing

Deep drawing provides a great application potential for the manufacturing of parts with complex shapes, even when it is scaled to the micro range. Two different foils out of the Al–Zr alloy with a thickness of about 15 μm were manufactured using a magnetron-sputtering process by applying substrate temperatures of 310 K and 433 K, respectively. These foils were used as blank material in micro deep drawing with a punch diameter of 0.75 mm to investigate the formability. Even though the materials show small ultimate strains in tensile tests, deep drawing was carried out successfully. Limit drawing ratios of 1.8 and at least 1.7 were reached for the material produced with a substrate temperature of 310 K and 433 K, respectively. These are even better results than those realized with Al-Sc alloys in former investigations. Comparison with deep drawing results of pure aluminum produced by conventional rolling shows the same achievable limit drawing ratio. This illustrates the good suitability of magnetron sputtering as a foil manufacturing process for micro sheet forming operations.