Cooling rate induced radial gradient structure in cylindrical metallic glasses

•Mechanical properties investigated by nanoindentation•Heat flow equation chosen during the casting process•Radial gradient structure induced by the cooling rate

The mechanical property dependence of a typical Zr52·5Cu17.9Ni14·6Al10Ti5 metallic glass on micro-structure has been investigated using nanoindentation. Heat flow equation was chosen to study cooling rate and the micro-structure during the casting process. Results show that cylindrical sample with larger dimension possesses a lower cooling rate, which leads to larger elastic modulus and higher hardness accordingly, and so is the center region compared to boundary in the cross section of a cylindrical specimen. To a certain extent, cylindrical metallic glasses are radial gradient structure induced by the cooling rate in a small range.