Search for novel amorphous alloys with high crystallization temperature by combinatorial arc plasma deposition

This paper describes a combinatorial search for novel amorphous alloys with high crystallization temperatures (Tx) using combinatorial arc plasma deposition (CAPD). The CAPD technique can deposit 1089 (33 × 33) thin film samples with different compositions on a substrate at one time. These 1089 samples on the substrate are individually referred to as CAPD samples and collectively referred to as a thin film library. Thin film libraries of Ir-Zr-Fe, Ir-Zr-Al, Mo-Zr-Al, Mo-Zr-Si, Ru-Zr-Fe and Ru-Zr-Si were deposited by CAPD. The compositions and phases of the CAPD samples were measured by energy dispersive X-ray fluorescence spectrometry and X-ray diffractometry, respectively. The results revealed that each library included amorphous CAPD samples. Since it is impossible to measure the Tx, fracture strength, fracture strain and Young's modulus of the CAPD samples by conventional measurement methods, larger samples having the same compositions as the amorphous CAPD samples were fabricated by a sputtering system. Since all CAPD samples of Ir-Zr-Fe and Ir-Zr-Al were too brittle, their corresponding sputter-deposited samples were not prepared. Sputter-deposited Mo-Zr-Al, Mo-Zr-Si, Ru-Zr-Fe and Ru-Zr-Si samples with ∼50 at.% Mo- or Ru-content were fabricated, and Tx and mechanical properties of these sputter-deposited samples were evaluated. All the sputter-deposited samples of Mo-Zr-Al and Mo-Zr-Si showed high Tx exceeding 973 K and as well as brittle characteristics. Ru50Zr35Fe10 samples showed high Tx exceeding 1273 K and a low fracture strength of 0.26 GPa. Samples of Ru51Zr5Si44 showed a high Tx of 923 K and a high fracture strength of 1.25 GPa.