Atomic-level structure and structure–property relationship in metallic glasses

Thermodynamic and kinetic aspects of the crystal to glass transformation in metallic materials

Zr–Al–Ni Amorphous Alloys with High Glass Transition Temperature and Significant Supercooled Liquid Region

Amorphous alloys exhibiting a wide supercooled liquid region above 100 K were found to form in a compositional range from 0 to 3%Co, 0 to 15%Ni and 10 to 23%Cu in Zr 65 Al 7.5 Cu 2.5 (Co 1-x-y Ni x Cu y ) 25 system by melt spinning. The temperature span ΔT x (=T x -T g ) between glass transition temperature (T g ) and crystallization temperature (T x ) reaches as large as 127 K for Zr 65 Al 7.5 Ni 10 Cu 17.5

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Amorphous Zr–Al–TM (TM=Co, Ni, Cu) Alloys with Significant Supercooled Liquid Region of Over 100 K

A new method for the preparation of amorphous alloys is the mechanical alloying process. So far, three amorphization reaction types were observed when this technique is used. Which reaction type occurs depends on the local conditions during the milling, such as impact energy and local temperature just after an impact. Amorphous alloys prepared by milling following different reaction types are compared to each other and to the corresponding melt-spun alloys. Furthermore, criteria for amorphization and a method to determine the glass forming range of TM-TM systems is given.

Amorphization by ball milling. A review

We present the results of a crystallization study in glassy Ni‐Zr. The alloys were prepared by melt spinning over the continuous range Ni20Zr80 to Ni70Zr30 including for the first time the region between Ni40Zr60 and Ni60Zr40. As expected we find that the glasses are most stable at and around the eutectic compositions, except that at the extreme Zr‐rich eutectic the glasses are destabilized by the premature precipitation of ω‐Zr. The products of crystallization indicate that the current crystalline phase diagram is incomplete: a new peritectoid phase must be added at the composition Ni2Zr.

Crystallization characteristics of Ni‐Zr metallic glasses from Ni20Zr80 to Ni70Zr30

The crystallization characteristics of glassy Cu‐Zr has been studied by differential scanning calorimetry, x‐ray diffraction, and measurement of electrical resistance and magnetic susceptibility. Our results allow us to remove many discrepancies between previously published data; they also suggest that the equiatomic Cu‐Zr does not exist as a single phase in the crystalline state. We observe parallel changes on crystallization between the magnetic susceptibility and the electrical resistance, which we interpret through changes in the d density of states.

Tu Guo‐hua

Papers

Crystallization characteristics of Ni‐Zr metallic glasses from Ni20Zr80 to Ni70Zr30

Crystallization characteristics of Cu‐Zr metallic glasses from Cu70Zr30 to Cu25Zr75

Superconductivity, magnetic susceptibility and thermal relaxation in amorphous CuZr