Influence of Y and Nb Addition on Crystallization Behavior and Mechanical Properties of Zr-Ni-Al-Cu-M Bulk Amorphous Alloys

Abstract

Bulk amorphous alloys are new class of materials with excellent mechanical and thermal properties. Bulk metallic glasses (BMGs) have wide range of application such as structural materials. Minor alloying additions play beneficial role in the production and properties of BMGs. The present study was conducted to investigate the effect of Y and Nb addition on activation energy, crystallization behavior, thermal and mechanical properties of Zr64.5Ni15.5Al11.5Cu8.5. Bulk amorphous ingots and sheets of three [Zr0.645Ni0.155Al0.115Cu0.085]100-xM2 (M = Y and Nb and x = 0, 2 at. %) alloys were produced by Cu mold casting technique. The alloys were characterized by XRD, DSC, SEM, FESEM and EDS. Activation energies were calculated. The alloy containing Y shows single stage crystallization while Nb addition shows double stage crystallization. The maximum activation energy calculated is 300 kJ/mol. Parameters describing thermal stability in these systems were determined from DSC data which improved as a result of these additives. Reduced glass transition temperature Trg and thermal parameters like g, d and b were improved by Y addition. The supercooled liquid region varies between 87-100 K. Hardness and elastic moduli were also improved. It was concluded that Y and Nb addition has beneficial effect on mechanical properties. Three phases NiZr2 and CuZr2 and Cu10Zr7 were identified by XRD and confirmed by EDS in the samples annealed at 823 K while the AlNiY ternary phase was detected in the alloy containing Y.

Atomic structure evolution during solidification of liquid niobium fromab initiomolecular dynamics simulations

“…Because of its refractory nature and resistance to corrosion, Nb has found various scientific and industrial applications. For instance, it has been widely used as an additive to improve the glass-forming ability (GFA) of various bulk metallic glasses [21][22][23][24][25][26][27]. In addition, the unique combination of material properties of niobium and niobium alloys is also used in the aerospace industry, where extreme working conditions are demanded [28].…”

Effect of laser remelting on microstructure and properties of WC reinforced Fe-based amorphous composite coatings by laser cladding

“…Subsequently, amorphous coatings were produced widely by surface modification techniques, such as plasma spraying [13,14], HVOF [15,16] and laser cladding [17][18][19]. These amorphous coatings exhibit many excellent properties, such as high hardness, high tensile strength, good wear and corrosion resistance and excellent magnetic properties [20][21][22].…”