Superplastic nanoforming of Pd-based amorphous alloy

Micromachines or Micro Electro Mechanical Systems (MEMS) of representative dimensions of less than 1 cubic mm are now being developed by various investigators. The purpose of this study is to establish a precision-forming process of MEMS parts by superplastic microforming of metallic glasses (Saotome and Inoue, 2000). Amorphous alloys are highly useful for realizing high-performance micro-actuators and microstructures due to their excellent characteristics as functional or structural materials, including isotropic homogeneity free from crystalline anisotropy on the micrometer and nanometer scales. The Pd40Cu30Ni10P20 amorphous alloy exhibits an obvious glass transition phenomenon at 577 K (T(g)) and a supercooled liquid state over a wide temperature range of 96 K (delta-T(x) = T(x) - T(g), where T(x) is the crystallization temperature) (Inoue and Nishiyama, 1996). In this paper, the macroscopic and microscopic deformation behavior is investigated in the supercooled liquid temperature range. An index of microformability is proposed to represent the geometrical transferability of the nanometer-sized die shape to the material. In addition, an application of the material to nanoforming is examined. (CSA)