Superplastic micro-forming of Zr65Cu17.5Ni10Al7.5 bulk metallic glass with silicon mold using hot embossing technology

The uniaxial compressive behavior of the Zr65Cu17.5Ni10Al7.5 bulk metallic glass has been studied at temperatures ranging from 673 to 723 K with a strain rate range between 5.0 × 10−4 s−1 and 1.0 × 10−1 s−1. The results indicate that the flow stress is below 50 MPa at temperatures above 683 K under strain rates below 1.0 × 10−3 s−1. Then the bulk metallic glass filling in the silicon mold with hot embossing technology has been investigated, and the appropriate superplastic forming conditions for micropart fabrication are explored experimentally. Mechanical grinding is put forward to remove the flash of the micropart accurately, then the silicon mold is dissolved in potassium hydroxide solution, and a good dimensional accuracy for a micro-spur gear with 0.1 module, 20 teeth and a spline structure in the core is obtained. It follows from the results that the superplastic micro-forming of Zr65Cu17.5Ni10Al7.5 bulk metallic glass with silicon mold is promising for manufacturing the high-performance complex micro amorphous components for micro electro-mechanical systems.