Effects of Si addition on the glass-forming ability, glass transition and crystallization behaviors of Ti40Zr10Cu36Pd14 bulk glassy alloy

The effects of small amounts of Si on the glass-forming ability, glass transition and crystallization behaviors of a Ti40Zr10Cu36Pd14 bulk glassy alloy were investigated. The addition of Si caused the decrease of glass-forming ability and the increase of the supercooled liquid region. The fragility of the alloys containing Si was higher than that of the Si-free alloy. In the glass transition process, both generation and annihilation of free volumes are suppressed by the addition of 1-3 at% Si. The activation energy for crystallization increases with increasing Si content, indicating the improvement of thermal stability. The crystallization structure of the alloys containing Si contents less than 4% consisted of six phases of CuTi2, Ti, Cu8Zr3, Cu4Ti3, TiZr and PdTi2.